living in Southern California (LA area, San Gabriel Valley)
Old home (Alhambra, CA): Excellent!
New home (Rosemead, CA...not far away from Alhambra, CA): between crappy and acceptable...sometimes no dropped call...sometimes a few dropped calls in a day! 3G speed not quite consistent (Sometimes 1.XMbps, sometimes 2xxkbps)
Places I usually go (like Wal-Mart next to my home, Fry's...etc.): Crappy...slow data or won't connect...sometimes calls can't go through on neither 2G or 3G.
School (Long Beach, CA):
2G: Excellent! (5 bars in most places on campus...Looks like AT&T is the only carrier that get reception in the lecture room of the business building...other carriers like Verizon, Sprint are all dead)
3G: Crappy (max 2-3bars)...much worse than the 2G ...Dropped call/call failed/no data on the first day of school...Speed can't exceed 1Mbps most of the time...No 3G in any indoor area...