For well over 10 years theres been one or 2 in temple bar on crown alley but I've never been inside any of them. I guess they must be ok if they've been around for so long.
Depends what you want - do you want funky clothes, designer clothes or what. Wa-wa charity shops often have John Rocha clothes left over from fashion shows (therefore mostly size 8!). Try charity shops in wealthy areas.