I have had a couple other pairs of Salomons (The XA mids and XA low) and these run a good half size bigger. I thought some thicker socks would make up the difference, but it's too much, they are noticeably bigger for some reason. Bummed cuz I have a couple runs in them already, so I am outta luck!
Traction wise they are fantastic in anything wet, snow or mud. I would go with something else for bone dry trails though.