600w digital ballast for $75.. good deal or don't bother?

I found an ad on craigslist for a used 600w Welthink digital for $75... He says he only used it for one cycle.. it has a 5 year warranty. Anyone know how much these cost new? Is $75 a steal for a slightly used ballast?

google it and see the diff in price. don't know much about welthink

ya id take i for 75 depending on how old .. if lightly used and semi new.. hell ya snatch it up