I was starting to think I just had really bad luck with these things.
Fortunately, when I went back to the boat today, it was working, at least as a charger. I didn't want to try to turn on the inverter, didn't feel like getting pissed off. At least I don't have to buy a replacement in the short term, which is good considering I'm going to be spending more money this time.
The Mastervolt was chosen best choice by Practical Sailor, but they also gave the Prosine good marks. Their testing was in a lab under ideal conditions and they were only looking at features and electrical output. My Prosine was pretty good for about a month too.
I'll have to choose between the Mastervolt and the sealed Outback FX, both look pretty good. I need to do a little more research, especially on the FX.
Thanks for the input.
-Eric