Coming from 3.5 years of 997 ownership, but two things I would say straight away:
1. Along with an Elise, the 911 is one of the classic driving experiences that everyone should have a try of once in their lives. All the weight out back makes for an incredibly intense and unique drive.
2. Read up on IMS and bore scoring. If you're in the unlucky 5-10%, then you'll need a slush fund of around £8K-£10K to get it up and running again.
Astounding cars, modern 911s.