I'm looking for a good, used power conditioner and surge protector. I would like a quality unit and I have seen many models on flea-bay from the likes of Furman, Panamax, WattBox and Monster, as well as a few others. Many are priced well under $100.00, but I really don't know which models are best. I have read about the Panamax MR 4300 (about $70.00, used, on flea-bay) and it seems to be a quality unit. Does anyone have any other recommendation on a quality unit? Thanks.