What's your experience purchasing used or demo rackets from TW? I'm not so picky that I need a new frame, or the latest and greatest. My assumption is that once I know what the specs are, I'm confident that if TW sells it, it's going to be pretty good. But, are they selling rackets that are generally in great shape, or are some of these rackets banged up, due to extensive use? I've demo'ed some and the rackets are always in at least good shape, so if that's an indicator of what I'll get with used, then I'm good. Thanks in advance.