I have been quite pleased with the Pioneer AVIC Z1. If you have the money to spend on it, that is the way to go. Notonly does it do navigation (and learns your driving habits for routing purposes) but it is XM and Sirius ready, can have an iPod hooked to it, reverse camera hooked to it, Bluetooth capable for making cell calls throught the unit handsfree. Whenever I put a CD into it, it records it to the built in hard drive so I can access it anytime I want. The navigation data is also on the built in hard drive. I paid 1350 for mine a couple of months ago. It is a double din installation, but I have seen on there a link to a place that sells a DD install kit for the 01-05 ST's... Not sure who has the link though. I upgraded to the Z1 from an AVIC N1 (flip out touchscreen navigation) that was moe expensive several years ago when I bought it. The Z1 is hands down better. Good Luck!
