Just upgraded from a '98 base with 5 speed to a '10 with pdk. Here are some observations.
1. Love the more aggressive look.
2. PDK without sport package has weird downshift behavior...even in manual mode. It doesn't just match revs temporally. It holds them for far too long. Need to use brakes to generate engine braking.
3. Suspension is much stiffer, even on the base model, but roll resistance seems about the same. I preferred the previous suspension which handled wonderfully without being quite so punishing on these crappy Michigan roads.
4. Acceleration is definitely better.
5. Fuel economy is likewise improved (got stuck in a line of construction traffic on way home from picking up car. Driving a constant 45mph in 7th saw 36 mpg!)
6. While top has a bit better insulation the car isn't any quieter as road noise, coming up through suspension is the main source of noise.
7. Top up/down at speed is wonderful.
8. Radio with PCM 3.0 and nav is still crap. I miss the Pioneer 6200NEX upgrade in the 986. Speakers on the other hand are very good (Bose) once I switched to linear. Otherwise it was just boomy with muffled midrange.
9. Soft touch paint peeling is annoying.
10. Glovebox is nice. Cupholders...meh.
11. Steering seems oddly overdamped at speed. Typically steering lightens up at higher speeds. It feels like Porsche, in an attempt to make the car feel more sporty, is adding artificial damping to the steering...making it firmer than even non-assisted steering.
P.S. I'm already pining away for a 981....S. Baby steps.