Just got these babies yesterday! I got to spend 30 minutes on the treadmill in my local shop. I tried some different models, and these where the most comfortable ones. I have a flat right foot, so I overpronate a great deal. I also tried a few other models: The Nike Lunaracers were nice but too narrow for my feet, and the Brooks Green Silence made me overpronate more for some reason. As soon as i put the Vivobarefoot on I cranked the treadmill up to 15km/h, which is fast for me, so I take that as a good sign. The plan is to use these frequently in my training, and hopefully their complete flatness will improve my technique also with padded shoes.
EDIT: After a few months of use I am very pleased with the shoes. There’s no way to heelstrike in them, even if you try. These first generation* Evo’s are extremely breathable. Actually the wind blows right through them. It’s definitely a summer shoe, despite looking warm and black. I use it as a road shoe. The soles traction is excellent for light trails too, but both the sole and the upper are very pliable, so if you kick a root or step on a hard stone, you might as well have been barefoot. Ouch. Of course water also runs right through the mesh.
The later model “Neo” is also a good shoe, slightly more comfortable, but also heavier and warmer. More suited for colder weather or trails I’d say . Both shoes are pretty minimal as running shoes go.
(*Second generation, the Evo II has a tighter mesh.)