I will admit it, there are really only a few times when I will wear a PFD. Paddling in cold weather, crossing big deep bodies of water, and of course white water kayaking. While I use a conventional WW PFD when hitting the rapids, I use the Onyx manual inflatable PFD for the rest of my PFD applications. When I am not using a PFD, it can be stored on the yak without taking up much space. When wearing it, it's very light weight, not hot, and doesn't constrict movement. When it needs to be inflated, you pull the handle, and it's inflated very quickly. I also like the fact when I am paddling in cold weather and have a heavier jacket on, this PFD will fit over it easily.

I used to use a bulky neoprene pfd from a certain big-box store. It was hot, stuffy and uncomfortable. And it's true that if a pfd is uncomfortable, you're not going to wear it. When my wife told me that she'd feel better if I'd wear my pfd while on the water, I decided I needed to get a nice one.
The reason I went with this Onyx was due completely to the fact that it is inflatable. There's no way it would be bulky or uncomfortable since it was deflated. That idea was spot on! I wear it out on every trip and have no problems with comfort. Sometimes I forget I have it on and leave the launch still wearing it.
I've never had to rearm it, but have done the process on a friend's, and it can be a little time consuming. There's also the issue of it going off in shallow water which could be problematic, but I haven't had that be an issue yet.
Overall, I think this is a great pfd that doesn't feel like a pfd!