The only issue with buying a used keyboard from ebay is that there may be a problem with it that requires a return/exchange. I've bought some Model Ms on ebay that were fine, but you never know if you'll get a bad board. I purchased a SIIG Minitouch on ebay that had to be exchanged because some of the keys didn't work, and that added a couple of weeks of time due to shipping the bad one back and having it replaced. If you don't mind the possible risk, then purchasing a keyboard on ebay should be fine.