said by morbo:
Please do share the company you are using and the details because I just priced a share plan on AT&T using 4 lines and 5GB data and unlimited everything else. Cost? $350
I think you need to check your math again. AT&T doesn't offer a 5GB shared plan. And a 6G/month shared plan with 4 phones is $230/month, before taxes.
The original poster may have an exceptionally good corporate rate. A 6G/month plan would cause me $213/month, before taxes.