New 2009 550i loaded incl. Sport Pack. Thinking about Doing the Dinan Engine Tuning package (Cold Air Intake, Exhaust, Throttle Box, Software) about $4,000. Any thoughts PRO or CON (i'm not really a techi car guy, just looking for some edge)

 

Intake for sure! They make the best intake for the E60.
Im Planning on getting one someday soon.
I dont know about the rest. Someone will chime in though.

 

De[pends on what you like, But the exhaust is incredible alone. If you dont want to spend all the money up front just do the software, stage 1 and the exhaust. I have both and they transform the car.

 

I did the exhaust and stage 1 software, LOVE it. Exhaust gives you an incredible exotic car sound without being obnoxious. The Dinan stuff will not turn your car into an M5 beater but it will definitely improve the cars dynamics and Dinan products flat out work. They fit right, work right, no other tuner comes close IMO.