They push out lots of updates and functions with text and calling will stop working properly.

Placing calls can be aggravating if you are in an area where wifi signals are weak and the phone is constantly switching between cell towers and wifi signal. The call will be dropped, sound muddled or just not get placed. Coverage has always been fine along the Wasatch Front and 1-15 corridor.

Overall though, if you don't need a phone to constantly be in contact with work or other important responsibilities, its great. I use the $10 plan without 3G coverage as I have a wifi signal available most everyday all day long. It is so cheap, I just look past the bugs. Go with the Moto X if you have the cash.