Weeee a GOOHMR moment, sort of. I friggin love my fivefinger shoes. On my third pair.
Before those, I had been running in regular running shoes. I got tendinitis once, and it kept coming back despite rest and NSAIDs. It got to the point that it hurt even just from a brisk walk, and so I gave myself a rest from running for a looong while. It blows to take a break from running. Felt restless yet guilty that I couldn't do much (biking/elliptical caused it to flare up that point as well, and brisk walking continued to be a problem).
Heard about vibrams, and figured $85 was worth the chance of better feet and being able to run again. I gave myself a few weeks to get used to them, first only wearing them around the house, then walking outside, etc. I hate wearing toe socks (the feeling of fabric between your toes!! ugh), but for whatever reason the fivefingers don't feel the same, they're like wearing slippers or something. Anyway, a few weeks later I took up running again. Haven't had a single problem with tendinitis in the former spot or anywhere else since. The biggest issue I've had from running in these are toe cramps (which subside quickly, and are probably just from forefoot running itself and not particularly the shoes) and blisters if I've been on a break. I find that the thin soles (like KSO) work better for running than thicker (like Bikila); there's just more flexibility. I once had something pierce the shoe - a thorn thing from a plant - but for whatever reason never glass (classy area with the occasional broken glass).
They are expensive compared to my usual purchase of on-sale running sneakers, but they're cheaper than those usual fancy running shoes. However, when they're worn out, they're really worn out - i.e. I wore through the sole of my first ones (KSO) completely. Another disadvantage is protection from cold weather, which I believe they addressed in a couple of models for cold sports. It doesn't matter here in SoCal, but it blew when I was in Nebraska in the winter.
People ask about them though, which can be a little awkward (but then again, I'm wearing something weird). For some reason the solid black ones I had turned more heads than my teal/yellow/camo ones now (??).
I wear them whenever I can, but I don't wear them for work in a clinic (unlike crocs, which are a pretty common weird shoe for people to wear there). I'm guessing they'd be fine for that type of work, but as weird shoes I don't want to be "unprofessional" even though my "professional" shoes are old sneakers and clogs.
For anyone looking for a deal on them, ebay can yield some people selling off ones that didn't fit them or they didn't like, but tons of the ebay sellers are selling knock-offs, often in colors vibram doesn't sell. I have to sift through quite a few, but I got my last (legit!) pair for $55, hardly used.
tl;dr: these shoes let me run again and aren't too expensive for what they are