Not too many issues. The earlier models were riddled with electronic issues.
For the years you are looking, try to find something with a CPO warranty. If not, try to find one with the most amount of service history.
You could also post up a prospective 7 you are looking at and we can give our opinions based on what we see.
Good luck with your search!
Last edited by 740-iLL; 10-18-2011 at 08:26 PM.