I have question about the GPS on HTC phones like HTC Desire Z. My question is if I don't have data plan or wifi would the GPS still works on the HTC phones? I have the Tmobile and I can only get the GPS to navigate if I have wifi. I was just wondering if I do get the HTC Desire Z which has the Sense UI would I be able to use GPS without having wifi. Like are the maps actually pre-loaded? I am still figuring why my TMobile G2 GPS does not work without wifi connection. Cause I thought HTC Desire Z was supposed to have preloaded GPS.