I have changed my exhaust to true duals and also installed a K & N air filter. Now I have to get a fuel management system installed. As far as the best quality and lowest price go should I install the Vance and Hines fuel pak, the Screamin Eagle Race Tuner or a power commander

There is an excellent resource for this type of thing. There is a usenet group called rec.motorcycles.harley where you can ask this question and get a ton of opinions. Go to Discussions - rec.motorcycles.harley | Google Groups

Read it for awhile. Do a Google search within the group for more info. Go to r.m.h FAQ v3.9 to see what the group is about. If you still want to ask your question, make sure you do an intro and buy a round for the bar first. That'll get you more answers. :)