(The only con I can think of is no warranty if something goes wrong, but if the price is right and the machine is in really good condition then I say the pros outweigh the cons. I would find out how many hours are on the machine, and if it's ever been crashed. Any maintenance and repair records would also be useful. Hope this helps.)
The only thing I would add would be to have a service tech look over the machine,they would know what to look for.Yeah will cost you a little money but it could save you a lot of money!
Just push the button,what's the worst that could happen.