I too use a Sevylor Trail Boat, the poor man's Alpacka. I've crossed lakes with it but it's a PITA to paddle and I'm a fairly experienced kayaker. You can minimize the tracking problem by breaking down the paddle, holding one blade in each hand, and paddling with a sort of butterfly stroke technique. That's what works for me. It makes a terrible snow sled but you can inflate just the floor and sleep on it, thus saving the weight of a sleep pad!! I also used one as a makeshift door for my Lunar Solo on a cold windy night. It's a true multiuse item. Even if you don't paddle one to Hawaii they're lots of fun.

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If you only travel on sunny days you will never reach your destination.*

* May not apply at certain latitudes in Canada and elsewhere.