Fit:
I rated this one as "fits" as expected, with the caveat that you know how Vibrams should fit. Most of us wear shoes that are too big for our feet. We have the typical "thumb's width" from the toe to the cap and a lot of times we choose a wide shoe when we don't have wide feet (I do have wide feet, but I prefer a wide shoe more because I like to allow my toes to splay out naturally when I run). Vibrams should fit snug, you don't want a thumb's width of extra material out in front because the shoe mimics a foot, not a shoe. I normally wear an 11.5 Wide in regular every day shoes and an 11 Wide in running shoes (running shoes should be a bit more snug and smaller is lighter), I am a 44 in Vibrams (10.5-11). I mistakenly followed the advice of some who said the new Vibrams were more true to normal shoe sizes even though I've been in 44 Vibrams since my first pair (the original KSO). Lesson learned.

Materials:
These seem similar, but more advanced than the KSOs I first bought over 10 years ago. Obviously the aggressive lugs on the soles are different, but the upper seems to be better constructed. It's hard to make a 1:1 comparison because the V Trails are more liketheir predecessor, the Spyridon, which I don't have experience with (I ran trails in the original KSO which has a relatively smooth sole so obviously these are going to be better on iffy terrain). I have no doubt that these will last at least as long as my original KSOs did.

Feel:
These Vibrams definitely have more padding than the KSO EVO which I run pavement and groomed surfaces on (the EVO feels almost but not quite naked), which is good when you encounter large rocks and roots on the trails. On softer surfaces such as dirt and grass they feel almost, but not quite too protective for Vibrams but that's the trade-off you make because when you hit a pointy rock or a gnarly root, you feel it, and make no mistake, it will be painful until you build your feet up some. You won't get injured per se (unless you ignore the instructions on how to transition to Vibrams from regular shoes), but you will feel every nasty bit and your foot will send signals to your brain which will make you panic...at first. Eventually, over a period of weeks (or for some, months), your feet will become stronger, tougher and adapted to the trails and your brain will chill out a little. That's when running in these seems to become pure bliss.

Grip:
Since this is a trail shoe, a review would be silly without talking about grip. I'd taken about 5 years off of running and just last year started back up. When I quit, I was running solely in the original KSO. I just began transitioning back into barefoot/minimalist running about 3 weeks ago. Given my previous experience, I felt comfortable going aggressive with the transition. 3 weeks after getting back into Vibrams, I ran a 5k Obstacle Course Race (Terrain Racing) in the V Trails. The grip is outstanding! At first, I was hesitant to trust it 100% and found myself blading and digging my feet into the mud trying to climb up the steeper mud hills. Once I realized that I wasn't getting as much traction when I did that and instead just planted my feet straight down onto the hill, I found that I could basically sprint up mud hills with no loss in traction as long as I ran the same as I would on pavement. There were times when it would have been easier to slide a little (coasting downhill, for example) but I had so much grip that I couldn't slide even when I wanted to.

As for the obstacles, there are a few places that I think the V Trails shine where many other OCR/Trail running shoes may have a tougher time, namely ropes, cargo nets, and balance beams or posts. In terms of the rope climbs, I think the thinner sole of the Vibram gave me better dexterity in looping the rope around my foot and clamping down on top of it (a standard rope climb technique) which meant I spent less time searching around for the rope to position it right. Cargo nets would probably be easier in an OCR specific shoe like the Salomon Speedcross because the Vibrams might flex a little too much there but against a typical trail running shoe Ill take the Vibrams again for the better dexterity. Balance beams and walking posts are where the Vibram really shined for me, both are effortless and made simple by retaining the flexibility for the foot to wrap over the edges of the obstacle to provide more grip and better incremental balance.

All in all, the V Trails are for me, the perfect trail and OCR shoe. They give me tons of grip, great foot dexterity, leave me no worries about losing my shoes in deep, thick mud and let me run with mostly the same form I would on pavement in my KSO EVOs. After this weekends OCR, the only thing on my body that does not hurt are my feet.