The PD 9100/9200 series are good converters. (The 9200 is equivalent to a 9100 plus the charge wizard--the wiz is just built in. As I think BFL13 was trying to say, the remote dongles are a bit different.) It looks as though, at least at Best Converter, the 9200 ones are slightly less expensive than the corresponding 9100 units.
In terms of repair, I might call Progressive Dynamics and see what they can do. They generally have quite decent support, and may be able to do factory repairs at a not unreasonable price or make some general recommendations as to whether it's a known failure mode etc.