I have had my P5 for about 50,000 miles. I installed a B&M short shifter which greatly increased performance and keeps the RPM up between gears. I have had no problems with the car in the year and a half I have had it. The only changes I made were to increase air flow to the engine by putting in a K&N drop in filter and cutting out the bottom of the air box which improved mileage by 1.5 mpg and bumped up the power by about 4 or 5 hp if you believe Import Tuner Magazine. I also changed to Lucas brand synthetic oil and gear lube. I put a hyperground system in as well, which does seem to assist acceleration and smooth out the idle to about 700rpm.
Styling is at the top of the list with the large driving lights and sporty looks. Mine already had tinted windows and it makes the silver model look downright sleek. The white background on the tach and speedo looks great.
Definitely put in a short-shifter as it reduces the throw between gears and also allows you to use the cup holders. A hyperground system clears up lag at off the line acceleration and also reduces idle speed while stopped. It also makes your lights brighter.
† Edmunds.com received the highest numerical score in the proprietary J.D. Power 2014 Third-Party Automotive Website Evaluation Study℠. Results based on responses from 3,381 responses, measuring 14 companies and measures third-party automotive website usefulness among new and used vehicle shoppers. Proprietary study results are based on experiences and perceptions of owners surveyed from January 2014. Your experiences may vary. Visit jdpower.com.