fs100 isn't full frame,its about a 1.52 crop, pretty much the same as nikon so any nikon DX lens WILL WORK like the tokina 11-16 and the tamron 17-50 (which i just got)
Also, the tokina will work on a full frame camera with very little if any noticeable vignette at 16mm. So, making the upgrade to FF isn't as painful with this lens as you don't have to buy another UWA right away haha.
So far pretty well, i have the kit (18-200) so the 17-50 will be used for like hand held stuff/close tripod stuff and ill keep the 18-200 for longer tripod shots. the 17-50 could be fun on the glide cam too.
I hear many people complain about the jello effect, which I find odd since I haven't had a problem with it on my 7D. As long as you're using solid support its a non-issue as far as I'm concerned. And on an fs100 it should REALLY be a non-issue since I'm told it isn't nearly as prone as the Canon DSLRs. The only way I can induce jello is if I'm shaking my camera violently...