I found a great deal on a optima rebreather on ebay. I have wanted one for a while but after winning the bid on ebay and then looking for an instructor, I was told by an instructor, that the type I got with metal hand sets are gaurranted to leak, and that I should upgrades and that the upgrades are rather expensive to the tune of about $2000.00. So the deal I thought I was getting may just be a huge piece of junk, does any one have any experiance with these units. did dive rite actually produce a rebreather that is of a poor quality that the main elecrtronics woould flood?