It depends if you are on an individual plan or family plan, and if you are on an individual unlimited grandfathered plan, you are probably better off staying there. I had a family plan with unlimited data on all the devices, and I decided to switch over to Next and saved a ton of money. I had been watching my data usage and found out that my 5 lines only used about 7GB total a month. I was paying over $300 a month. I switched to the 10GB shared plan and it went down to under $200 a month. Now they have the special running that if you do the 15GB plan, you get 30GB. So I upped to it and only pay $30 more. It is not unlimited... but 5 lines sharing 30GB is more than I would ever use and I could tether on every single phone which is cool.

And as a bonus... I upgraded all the phones (with 2yr contract discount price) just before I switched over to the mobile share value plan. So I am still on contract... but I am not paying for any of the phone anymore. I think this is some kind of loophole.. but I am not complaining. I saved $1800 already for the next 2 years!