I just got my unlocked iPhone 4. However, the reception is much worse compared to iPhone 3GS and 3G in the same place with same SIM-cards on two different carriers. iPhone 4 bars are always 3-5 smaller. Also, very often it is impossible to get service. I don't think this has anything to do with this widely known problem of touching iPhone since the problem is there even when I don't touch the iPhone. I have tried to restore the software and reset settings. Is there anything I could still try? Is it time to call Apple?