Yeah, give em a try.
I've been using bitskins for around 2 years for selling & buying skins. For me sales commission fee is 5%, while new comers might have 15% commission fee, which will decrease the more you earn selling in bitskins. The website UI is outdated compared to others, but I haven't faced any problems so far.
I've just opened an account in dmarket, lured by it's low sales commission. Not so much items in discount tbh, but it's a great website tbh.
I haven't tried skinbaron yet, but it seems legit to me from outside, and is one of the most popular skin market website in the world currently.