Okay, I've tried to read through all the posts on this topic and my head is spinning. I'm about to get a new car. I definitely want some sort of navigation system, but paying $2,000+ doesn't really make sense. I have no idea how well the different systems work, including the Seidio/Tom Tom/ etc. systems for the Treo.

So: here's what I want my system to do, below. My questions are: in light of what I describe below, what system is best? Is there a system that can make use of the Treo 650 and won't be a memory hog, or should I get one separate from the Treo? I want it to:

1. Be mounted either on the windshield or dash.
2. Be quick and accurate.
3. I want to be able to talk on my phone wirelessly (probably thru Bluetooth) at the same time as I'm using the GPS system (raising the question of if it's a bluetooth system, can I talk on the bluetooth car system at the same time?), and also allow incoming calls while I use it for nav.
4. I want the program to speak to me and tell me where to go.
5. Not reset my phone randomly.
6. Charge my phone while it's in the GPS or whatever cradle.
7. Not eat up all my Treo's memory. I've only got 4 mb or so left.

Maybe I need a separate, non-Treo nav system for all this, but does anyone have any recommendations? I see a lot of different threads on this issue overall but I'm just trying to understand whether I should 1) use my Treo to nav, 2) if so, what system is most reliable and advanced and won't prevent me from using the phone function, and 3) if I shouldn't use the Treo, what nav system is best.

Hope that all makes sense...thanks.