Well first off, you've picked two great color choices! Second, be ready for lots of looks, comments and make sure to keep a drool rag handy to wipe off any excess....

Now, on with the show. Make sure to check that the rectifier recall has been completed. Some had some brake light issues. The '12 is notorious for having lifter issues so may want to check if there were issues or they repaired before there were issues. Not all of us have had lifter problems but that seems be the one constant that keeps coming up. I've had radio issues (had it replaced under warranty) and the amp in the left saddlebag can cause problems if the double stick tape (yes, I said tape) ever lets go.
You may want to do a search on the forum to find more as we have all had some kind of issue (from minor to major) with our '12 SESGs. However, so far it's the best HD product I've had the pleasure of owning (and I've had quite a few). Good luck with the search in a couple of years. You can ALWAYS find a garage queen for sale or a good middle/high mileage option that's been well taken care of.