I've bought Postfinance payment gateway plugin for Wordpress from CustomWeb for 200$ / year! Which should be one of the most expensive Wordpress plugin in the world!
My website's performance decreased by 90% (no kidding). I am not a Wordpress noob and I know my business. I sent them analysis results (using other plugins like P3 (Plugin Performance Profiler)), showing them the problem was with their plugin and that they should do something to improve it. They refused and kept telling me that it was a problem with my server. I've sent them server analysis results, proving that the server was not the root cause. They refused to give me any support and I did not get my money back (althoug there is a refund policy). Be careful with this company, they just want your money.
Total nonsense on this one. The refund was sent, and also yes there were some bugs at first in the theme, but they have been solved. However the refund was already sent.