DaltonF

Just bought my first Audi a couple of weeks ago. Its a 2005.5 S4 and has had a little bit of work done to it. I'd like to tune the car up with a new ignition system and was wondering what would be the best brands/set-up to use. The car has a stage 2 tune and a few other "bolt ons". The car has 85,000 miles. Should I go with OEM or something high performance? I haven't had much luck searching the forums so I apologize if this has already been answered elsewhere.