Warning: Long and rambling.
I haven't paddled the Alpacka as much as the Packlite, but I can say a bit more. I did go to Alpacka and test sit a few of the models and options (before advising my buddy who now has the very boat I'd like, but really that's not why!)
So the one I have paddled (and will buy) is sort of the basic workhorse. It's not meant for anything super specific. They do have boats that are optimized for whitewater (if I were still in my 20's-30's I would love to give one a go in the same places I took my "old fashioned" kayak), and they have some that are optimized for hauling gear (bikes, hunting spoils, etc.). They also have one (Scout) that is super tiny for, say, backpacking and just crossing a placid stream to get to the other side. The Alpacka is the most generic (but then you could also say versatile).
If one settles on the Alpacka, then it comes in four sizes. If you are used to a regular boat they will all feel crazy short, like you are "wearing" them. Not in the strapped in to your whitewater boat way, but just that your feet come pretty much to the end of the boat. But not in a cramped way, just surprising. They are all kinda beamy (my biggest paddling complaint but I guess you just can't make a 20" inflatable). I can fit in the smallest of the four, but with the next size up (Yak) I have a little extra room in the bow. They make an inflatable cushion you can put there for a foot rest, but you could also have that be a gear bag. There is a standard inflatable back cushion, or an optional back strap (oddly, I found the cushion more comfortable even though I was sure the strap would be better - so did my buddy).
Next you can get a bow bag. A soft bag with a waterproof zipper that sits on top of the bow, strapped on. My Packlite came with a mesh one and it's so handy! I keep water, a sweater, my camera, etc. in it and you can reach it pretty easily (unless you get a longer boat, then I suppose maybe not). The larger bow bag is my preference because the zipper is more across the aft edge (like my Packlite bag) whereas on the smaller one it goes diagonally across the top.
Other options are for spray decks. These would of course be nice for real whitewater. Wind waves seem to pretty much stay out due to the high tubes (granted I have not had it out in huge winds). The cruiser deck is removable, but doesn't really give you a shaped cockpit; the whole deck just kind of diagonally closes around you. The whitewtaer deck uses some PVC tubing (inside, you don't really see it) to make an oval cockpit like you'd be used to on a whitewater boat. So you can have the deck on with the open cockpit, or add the sprayskirt. They make a removable whitewater deck now too, although there is some evidence left on the rim of the kayak when you have it off. It does add a bit of fiddliness to get the boat ready, but I liked the whitewater deck. it would be (obviously) good for whitewater but also for cold or rainy climates.
You can also add various thigh strap methods and things like that. For just normal paddling, the boat actually "fits" pretty nicely even without straps, but I am a fan of being more "locked in" on whitewater.
I don't have anyone to paddle whitewater with these days, so I don't see myself paddling serious whitewater. If I were, I'd definitely consider one of the whitewater-specific boats. I would think that for Class II, with maybe an occasional III thrown in, the Alpacka with spraydeck would work (maybe even open on Class II and under). There are some super keen paddlers (of all kinds) at Alpacka so they could give good advice.
Oh, and they also have these storage bags that fit *inside* the boat's tubes. There is a zipper that opens the tube and then a special shaped dry bag that goes in, you zip it back up and away you go. I wouldn't get these because I'm not planning any long expeditions, and you have to deflate the boat (not entirely but I mean you are opening the tube) to get into the bags. Not great for grabbing a sandwich or sweater. You can have this added later to an existing boat if you change your mind.
They inflate via a tiny little "pillowcase" of nylon. You pull it through the air to fill it and then push that air into the boat. The cool thing is you can bring this along vs. a big plastic pump. But of course you can also use other pumps, be they foot, electric, or whatever. But so many times I wish I could have topped off my Packlite enroute (the Aplacka also probably doesn't need topping off as much; the Packlite is fairly low volume so when it shrinks due to cold water it's starting to fold in half on you!).
So when I was there I mainly focused on the Scout (tiny boat, which I ruled out pretty quickly), and the various Alpacka models (i.e. which size would I want). I ruled out the largest one, which left the smaller three sizes. The smallest one just fit, the next one up gave me plenty of extra room but I could still reach the bow bag and foot cushion, and the third one just seemed like more boat than necessary (for my mostly day trips). Obviously that is totally subjective. I'm also not super tall.
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I DO appreciate a good paddle, and for that there is no downside (except money). A good paddle takes up no more room and is no harder to carry than a mediocre one. Bring it on!
My buddy already had a two-part Eddyline Mid-Swift (he had a hard, day touring kayak before the Alpacka) and that is a very nice paddle. Light as a feather, not a bit of slop in the attachment, easily adjustable (feathering angle), and it has these reflective "stripes" in the blades (which you can get in a number of colors) that really catch the sun and make you visible. It is not adjustable in length, but you can order various lengths. I think they also make four-part paddles. Of course the more joints the more weight, but I have a four part (cheapie) Packlite paddle (which is actually Packheavy) and that does allow it to store in the tire locker. They also make a few other blade styles than the Mid-Swift. Being an old-fashioned (I guess?) higher angle paddler I might like the Pro Swift.
Werner is also making some paddles that look like they might be nice for pack rafting, including a four-part length-adjustable packrafting specific paddle. IIRC it's not as light as the Mid-Swift. They of course make lots of other paddles too.
And I "air tried" a couple of Aqua-Bound paddles at the Alpacka store - they seemed like contenders too.
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BTW, my buddy also RV's and had a very nice day touring hard kayak that he was very fond of. It was his first boat, so he didn't have anything to compare to, but I paddled it and it was really fun. BUT, he found that he was not using it (or when we went paddling together he was groaning all the way back up to the car carrying it). And he actually had it mounted to the roof of his tow car so it was not that bad to get on and off the vehicle. Granted he's not a very dedicated paddler, so he was fairly easily discouraged. But anyway, he just kind of quit using it, or only wanted to do places that were right next to the parking lot.
Now he has the Alpacka and loves it. Granted, he could have left himself in the dust in his hard kayak. And he's not a lifelong paddler, so his opinions would come from a different place than yours, deppstein. But for him it's great as when it's put away it's in a compartment (vs. weathering away on the roof), and he no longer minds hiking up to that mountain lake, or doing the "shuttle" by walking a half mile with the boat. Also he likes how comfortable it is for "kicking back."
I definitely notice that it's not as purely good to paddle as a real canoe or kayak. I mean, it's like shuffling along on snowshoes vs. gliding on skiis. But for me right now it's something that I'll get out on the water in much more often, and go more "odd" places which I'm really enjoying. I guess kind of like how I enjoyed snowshoes cause you could just put them on and go anywhere (vs. organized ski trails). If it's early evening (summer) and I see a cool spot? Out comes the boat! Walk upstream 3/4 of a mile to put in and then paddle back? (winding river so I get more than 3/4 mile on the water) Sure!
So I guess for me it's not so much comparing this boat to a "real" boat because it's just not the same. It's more just looking at the experiences it gives me as a stand-alone thing. And... it's just kind of fun. Like paddling a big inflatable jelly bean

It probably helped that I had a paddling hiatus so wasn't coming straight from some really great, fast, canoe or kayak. Don't step out of your Jensen and into an Alpacka
