it really all depends on signal quality. the better view of the sky=faster lock.....
Asssisted gps. the agps(PDE) server provides orbit info for the gps sats, so the phone doesn't have to do as much work to get a
fix, and when it's working good it will actually give the phone a lock just off the cell tower (rough) which will speed up accurate locks from gps. the most complete dissusion on the topic is probly in the titan section.
http://forum.ppcgeeks.com/showthread.php?t=17032
titan and vogue are basically the same.