I'm not sure if you can make a reasonable comparison of speed if your device doesn't support LTE...
Also, California is a pretty big state. In LA, we use a lot of different data devices in the office from Verizon (mostly the Pantech ULM290s), AT&T, and T-Mobile (we dropped Sprint a couple years ago - they were terrible). T-Mobile performs great down here. I haven't had problems w/ my T-Mobile LTE devices (I carry an unlocked 5S, Nexus 4, and iPad Mini) when I'm up north either.
Also, California is a pretty big state. In LA, we use a lot of different data devices in the office from Verizon (mostly the Pantech ULM290s), AT&T, and T-Mobile (we dropped Sprint a couple years ago - they were terrible). T-Mobile performs great down here. I haven't had problems w/ my T-Mobile LTE devices (I carry an unlocked 5S, Nexus 4, and iPad Mini) when I'm up north either.