As it turns out, I got given a free pair of the original FluidFeel shoes. I didn't think I would like them much, as this sort of heavily cushioned shoe is not what I usually choose to run in. But I really liked them, particularly on days when my feet felt sore and tired.
Fast forward a year or so, and I'm training for my first hundred miler. I had intended to wear my favorite daily running shoe, the Montrail FluidFlex II, but after a couple of big mileage weeks, it was clear to me that I needed a beefier shoe with more protection to run 100 miles. I immediately thought of the FluidFeel, but my pair had big holes in the upper from a lot of running through snow. Figured I would take a chance and order a pair of the updated FluidFeel, hoping nothing much had changed. The shoes arrived on the Tuesday before race start on Friday morning, so I never got a chance to run in them. I tried them on, and the fit and feel felt pretty much exactly the same as the original version. Hooray!
The race went perfectly (at least in terms of footwear). The Bighorn course had pretty much every kind of terrain -- dry & dusty, rocky sections, lots of river crossings, mud, snow, huge puddles. To my great relief the shoes performed great in all conditions, and despite having never run in the shoes before, I didn't have any blisters or foot issues at all.
I've since tried a couple of other shoes with 100-mile distances in mind, and haven't found anything that works as well as these.
About the only criticisms that I have are (1) that the laces could be an inch or two longer, and (2) the fabric on the uppers is a little fragile, and gets easily frayed by abrasion on rocks.