I ran in the last version of the Agravic Speed Trail, and it was light, and fast but I couldn't find a good fit between an 8.5 and 9 men's. The sizing was just weird. I knew the Agravic TT was coming out in February so I waited and I am really happy that I did! The shoe was reported to be more stable and I would agree. The midsole has a wider profile around the mid foot and the heal than the Speed Trail. The Continental rubber is very grippy! The fit is much improved, although I still think it is a tad wide in the toe box. I also wish the tongue was a little bit longer because I get some lace bite around the front of the ankle and the heel still feels like I am not entirely locked down. It's a bit disappointing for a shoe that is this expensive. I don't run a lot on trails but when I do, it's pretty rocky and technical. Hopefully this review can help someone. I am not sure I would purchase another pair.