Do not buy a Microcell. They are not fit for purpose.
I have owned 3 Microcells, and each one has lasted just over 12 months before they just stop working. Mine just died, again. IMO this is outrageous on soooo many fronts.
Customer Service is no help. They simply advize to buy a new one. I've already spent around $600 to make up for AT&T's lousy coverage in my area (greater Boston, MA).
Out of desperation, I just bought a "used" one on Ebay and unfortunately the original owner did not deactivate prior to selling. And for some reason is unable (or unwilling) to deactivate for me. So I called AT&T today and they gave me some blabla story about not being able to determine who the owner was in order for them to deactivate the device. Ofcourse they know who originally activated it. And ofcourse they can deactivate it. They just don't want to so that I have to spend another $150 to buy a new one! Like I said....OUTRAGEOUS.
Net net, I strongly advize agaist buying one of these. Try Verizon or a carrier different instead. They currently offer lots of incentives to move from AT&T. You'll be better off in the end, and maybe AT&T will get the message.