What exactly is 1xRTT? Verizon's version of EDGE? I do know it performs horribly, seemingly much slower than EDGE.
3G is darned fast on a phone that supports 3G data only (as in not 4G capable) but for some unforseen reason the experience is neutered on a 4G LTE capable device, often performing at near dial-up rates of 56k or worse. That never made any sense. I got a great example of that yesterday. Couldn't even use the Web browser on my Note 3 with three bars of 3G. Play store timed out, and a single 1mb download took half an hour to complete.