I actually have both. I initially wanted the nonstick, but at the time, due to the tsunami I had to take what I could get before everything was gone, so I ended up with the nonstick. Then, a few months back I actually won the "UL" version on the Trail Groove site!
As far as the weight savings, it is not much, something like just under an oz, but, a weight savings is a weight savings...
So, what will you be using it for? Just boiling water? I would say go for the "UL" version. If you plan to cook in it, the nonstick version may be a better choice.