I got a G900V and I use a china telecom SIM.
The phone can find the cell and both voice and data worked well.
The network mode was 3G, that's CDMA2000.
The problem is the download speed is low, less than 10KB/s, but if I use a Verizon version iPhone 5s to try, the download speed is much better.
Does anyone has some clues for this?