After I have installed latest ROM, I am not able to get proper 3g connection. I never get stable network connection when I enabled 3g. I cannot even make a call. I have restarted cell after disabling the data but did not work. Finally I tried disabling 3g and I got stable connection but data is of 2g. I am using only one Sim. Just to update I have downloaded zip files twice thinking the earlier might be corrupted but did not get the result . I have also flashed performance ROM.
Since the 2G connection is working perfectly but not 3G so obviously its because of your service provider who is not providing better 3G connectivity in your area.
I myself use 3G on this rom and almost 1300 other people have also used the rom but they never faced 3G connectivity issue.
Try using any other sim card on your device and run 3G on it and then report to me.