I've never tried to sell my clothes at Kind Exchange so I can't comment on all the hate from previous reviews but as a shopper, I've always been thrilled with this store (and their other locations). In fact, I try to avoid them for the most part because I can't seem to stop buying things there.
The selection is great. I've found some cute pieces for as low as $9 and some designer pieces for insanely cheap prices. ($25 for a brand new French Connection dress - what?!) I guess your success depends on your style but I've always gone home happy.