Buying a used Control 24. Is it still a good idea? Owners or ex-owners please help!

[Intini]

Hi!
I use PT HD and was wondering if it was worth buying a used Control 24 to mix my projects. I think I can get one for a good price and then later I can "upgrade" to a C|24 or an to a D-Command. I would appreciate some words from owners or ex-owners of the Control 24 saying if it is a good idea or not and what to look for in the used unit I am going to buy, such as issues with PSU, scribbles, etc. Is there a way to quickly check all possible issues without connection to Pro Tools? I don't want to find out something wrong only when I get back home!