If you go back and read my 'race reports' over the years, you'll see that my go-to footwear, IF I use footwear, has been VFFs. All my paved runs and races have been barefoot, but my VFFs have served me well on multiple trail marathons and 50Ks, two 50 Milers, and on the Burning River 100 Milers (which I DNFed on, but they got me to Mile 67—the problem was not my feet or footwear).
I've been using VFFs for five or six years, ever since I've been running barefoot. I use the traditional KSOs (“keep stuff out”) that come up over the top of the foot. Vibram has since come out with multiple new brands, some of which are built like tanks, other of which are made to look more shoe-ish, and some of which even offer arch support (!) none of which I recommend. And there are VFF imitators out there too, most of which seem to opt for the more tank-like design. But I recommend the old-school KSOs. You want minimal protection in your minimalist footwear. VFF KSOs offer a good thin rubber-like sole, flexible, yet sturdy enough to keep sharp rocks and sticks at bay. That is, you'll still feel what's underneath you, but you'll avoid and cuts or contusions.
I prefer to wear huaraches—I like having my feet to the open air, but they just do not function well in wet weather. The rubber soles get slippery. VFFs however (especially KSOs) work great in wet weather. They cling to your feet, wet or dry. Most of my running and races has been in either Michigan or Oregon, both wet states. On one of my Michigan 50Ms, the course was laid out so as to be as annoying as possible, with many stream crossings, and even wading through a lake. Other runners had to plan out shoe changes along the way, but I could just breeze on through. And the Hagg Lake 50K Mud Run in Oregon was no problem, though I did slip a bit. KSOs don't have a lot of traction.
One disadvantage VFFs have is cold weather: They just do not hold heat at all, and in fact seem to be colder because the toes are separated out in individual sockets, rather than huddling together for warmth. For colder weather running, I've been using Merrills, which are an actual shoe and enclose the whole foot [see my latest review of them on this blog].
Another thing about VFFs is that they get strongly smelly. You can wear the Injinji toed socks—either thicker cotton, or a thin nylon. The thin nylon ones will work for keeping the sweat smell to a minimum, but note that one, they're pricey ($12-15 for one pair!) and two, they wear out and tear quickly. The thicker ones last longer, but then you'll have to bump up your VFF shoe size, meaning you'll either have to wear socks all the time, or buy another pair for wearing barefoot. The thicker socks will also had some warmth, though note, I recommend buying socks a size bigger than what they recommend on the package. But I don't wear socks anymore. And there are ways to combat the smell, though they involve chemicals.
Also, I should mention this. My first pair of VFFs fit fine, and were always comfortable, so much so that I keep wearing them even though they're almost falling apart. My newer pair, which I won in the Bigfoot 50K for being the first, and only, person to finish in VFFs, fit basically the same, but something inside rubs against the skin on the ball of my left foot, causing a blister or even a cut on longer runs. I think this would go away if I used them more. But I should note that this happened to a friend of mine with his VFFs too. Try a new pair out slowly, and check for hot spots. If so, apply some duct tape to the area.
Unfortunately, Vibram just got hit with a class action lawsuit, claiming that their claim that VFFs will make your feet stronger isn't true. I actually think it is true, and the real problem is idiots going out and running in them like they would in 'regular' running shoes, with the hard heel strike and a wide stride. You can't do that. The best way to learn how to run in VFFs (and actually to re-learn how we should be running) is to run barefoot first, or at least in conjunction with VFF running). I've never had a problem, though I now don't like running on pavement in VFFs, and don't recommend it. If you're in the city, just run barefoot, and/or use a thin huarache, like the Xeros (please see my reviews of them on this blog).
Actually, those people that get injured running in VFFs may have just been misinformed by the idiots who work at running stores but who know nothing of running barefoot and/or minimalist, but pretend to—if buying minimalist footwear from a store, make sure you ask the person selling them to you if she or he actually runs in them).
In any case, the only people who 'won' in that class action lawsuit were the lawyers. I'd like to have a class action lawsuit against the shoe companies who claim 'running shoes' are good for you. Where's the proof? Where's the science?
But, I rant. Here's the deal:
The Vibram Five Fingers KSOs are my top overall favorite minimalist running footwear. First prize!