Get one that has had the top replaced or a new top fitted.
Get one that has been looked after and not abused. Look for water in the trunk under the passenger side foam block.
If you get left at the lights by a Honda Civic you'll wish you had got an SRT or an auto tranny NA.
An after market SC pulley on an SRT is quite possibly a ticking time bomb, if it has one of these pulleys make sure the LM21 pulley shield is fitted.
Get a low mileage SRT or regret it later. Get one with two working keys and a spare SKREEM if possible.