Going to look at a used B-52 Matrix 2000 Setup, What to look for?

An acquaintance of mine is selling a used B-52 Matrix 2000 System. I don't know the man well, he claims it has only been used a handful of times. I've done research and seen some of the problems people have had. I know this system has been out for awhile. But I'm not sure when this was purchased and don't want to buy a system to have it fail. Any tips on what to look for?

He's asking $875 for it.

Would this work well hooked straight to a Hercules 4-mx?

Thanks,
Zach

never heard good things from B52, sorry man.