I bought and used a Korean version of Galaxy Note (LTE with DMB) on SKT network in Korea for a while. I liked it so much that I decided to use back home (USA) on my ATT 3G unlimited plan I keep for iPhone 3GS. Back home, ATT store rep provided me with a sim card, which worked fine for voice. But the internet speed is only 44 kbps with 'G' sign on the top notification area. I tried a lot of APN settings, reboots and hours of tech support form both ATT and SKT in Korea. No success so far. SKT tech support said the phone carries neither country lock nor carrier lock, which seems to be true considering I can use voice on ATT without any problem. They insisted that I need to talk to ATT. When I tried to replace LTE B5 band originally set by SKT (?) with other LTE or WCDMA in the 'band selection', it won't allow it. Only 'Automatic' and 'GSM All' are possible to select. I used SGS Secrete Code app. Phone info: PDA : E160S.EK25.0152 PHONE : E160S.EK24.1917.ST MOVINAND : EK25 BUILD : Fri Nov 25 01:58:03 KST 2011 I wonder if the hardware itself has limitation or it can be solved by some kind of setting or software approach. Please help. BTW, I like the phone very much. I think it's a tablet killer.