I have a couple, I think they're ok. Steer clear of the A-series (A500 and so on). The S500 is their better mid-tower and their Q500 is a fairly nice full tower, although a lot of people are liking the Antec 1030SX for its four 80mm fan positions. The Inwins are pretty sturdy cases and make a good starting point for modifications like blowholes.
Which one are you thinking about?