Let's how many consumer customers will pay this price. ATT, you have to do better, when it comes to plans. Following their current price of $10 per gig is ridiculous, when you consider all the fees you still have to pay. Waive the additional line fee for at least two extra lines, or something. The average bill be ridiculous, when it's all said and done. Better yet, reduce the 30 gig to $150, 50 gig to $250, with the $15 overage. That's better than what they're offering.
It doesnt matter, their pricing is still insane. T-Mobile Small business plans give you 5GB high speed / throttled after that for $24.99, so 10 would be 50GB, which would be $249.99. I know that is 5GB per line and not a true Shared 50GB, but I'm sure saving $250.00 per month, or $6000 over a 2 year contract would sway most businesses.
I'm sure what would really sway customer is actually being able to use their phone to make phone calls or surf the web. Its great to save $6000 but if you can't use your phone then it doesn't really matter how much many you save.
If you're in a major metroplex (which I assume most small businesses are) you're pretty well covered by T-Mobile. I know at least there isn't a place in the entire DFW area that I can't get their HSPA+ signal. YMMV, of course.