What is the best after market navigation system for an Acura TSX 08 or 09 model?

Depends on what you are looking for. In my opinion, I like the Pioneer navigation units the best. they are the most user friendly with the GUI and the Ipod/Iphone interface. The only con is that the startup times on the units are a little slow (around 30-45 seconds). I currently have an AVIC-F700BT unit installed but am looking to upgrade to the AVICZ-110BT (would hihgly recomend theis unit over the one i currently have).