I have been using Exede for just over 2 years (at like $80/month) for 15GB cap and now 25GB cap. I acquired my first Mobley 2 months ago and have been happily streaming and updating my PCs, and doing everything else I feel like ever since. Yesterday I took deliver of my 2nd Mobley so that the PCs and DISH DVR in the basement can have their own AP and I'm using my original on the main floor for the mobile devices and Amazon FireTV. The monthly fee - $45 and both have unlimited data. Exede will be out the door by July 28th.
Hopefully AT&T doesn't change their unlimited data policy any time soon. I'm not sure why folks were having issues acquiring Mobleys; unless it's because you weren't already ATT customers, but I ordered 2 direct online and had them within 5 days each and they arrived activated and ready to go.