I couldn't agree more with gold panda. All of their products are engineered to work in unison. I have a stage 1 dinan, except I have a Remus exhaust. Remus and Dinan use the same manufacturing company to make their exhaust. Essentially they are the same exhausts with different names.
For exterior and interior mods, I have only AC Schnitzer.
Hands down, the dinan engine mods are top of the line and backed by them.