I think the one main issue with the earlier releases of the camera was the "light leak issue". Just do a google search on what serial number ranges were affected ad compare your serial number (on the bottom of your camera).
"Issue", which affects your metering if you have your lens cap on while shining a flashlight at the top of your camera. I wound't worry too much about that, unless that's your typical shooting scenario.
hey...he asked what to check for.