Summary

one is cut to be printed on the back the other is cut to be printed on t he face.. the face is better if u can use smaller layers for a better case .. as the over hang inside the phone can be printed at the 90degreese.. (the outside hass a curve to match the phone)
if you have clear tpu print the one on the back .. i beefed up the back of the phone so you coud sink it in to the buildplate and still get the inside curve but the outside is flat the width is 1.2 sink it in to the build plate to get the single layer bottom :) i also reduced the amount of distance on the 90 degree over hang .. its still there but with a small chamfer that allows it to work (less snappy feeling but still snaps in there )