Just wanted to update on my "hack" for the vent mount. Been very solid so far. I have some concern over the longevity of the cable ties, but honestly, it's a very minor concern. Very little movement of the phone, great location being on the air vent (especially in the summertime, keeps it cool).
I can post pics if anyone wants to see, but I'm glad I went that route. Leaves the windshield mount available for when I'm in a company vehicle or my wifes car.
Current: HTC Droid Incredible 2 and Motorola Droid 2 Global.
Former: Blackberry Bold 9700, iPhone 3G, HTC Fuze, Samsung Epix, Treo 750, Cingular 8525, Cingular 8125, Audiovox SMT5600, other non-important junk.