corbinam
Moderator
I agree with what Silaria posted. I don't have anything other than anecdotal evidence about them, but in my agility circle a lot of top competitors have them and swear by them. For me, it probably is more of a "can't hurt" type of attitude. But, I do agree that it seems to keep their muscles warm which I like if there's a short time in between runs and it's chilly.