I was in Hong Kong last week and got to test out the razr maxx's gsm radios. The whole process was pretty painless. I purchased a prepaid (micro)sim card at HK airport, took out my 4G verizon sim, inserted the local sim card, switched mobile network to gsm/utms and I was connected to the carrier's 3g network. Overall I was pretty pleased. The reception was good and I got decent speeds. There were a couple of dropped signals, but I always reconnected seconds later. When I got back to the states, I popped back in my 4g sim card and reconnected to verizon's network with no problems what so ever. It was pretty sweet.