Two of my buddies both bought inflatable yaks a couple years ago... Fast forward 2 years to the present and they have hard yaks now and sold their inflatables if that tells you anything. The times we went paddling, It took forever to set them up and take them down while I was ready to roll (or float) in seconds with my hard yak. I would look into a tandem kayak or even a canoe if I were you. While the deflated size seems like a plus, I don't think it's worth the time wasted for setup and takedown. Not to mention, having to worry about airing out the thing to keep it from getting the funk. Get a decent roof rack and saddles and you'll be good to go. That's just my opinion though after experience on trips with my buddies and their inflatables.
Also, an inflated kayak can fly out of the back of a truck on the highway easily if not properly tied down... Lol fortunately for my buddy, his neighbor happened to be the person who found it in the median of the interstate and his neighbor's garage door happened to be open when he drove by. What are the chances of that lol?!?