Every network has black spots. I notice it alot when Im in the UK. Where my Mum lives has good O2 and rubbish Vodafone coverage. Other places its the opposite.
Sure signal is a good solution for just in the home but you have to shell out quite a hefty price for it . Once you have it though you do get full 3G
throughout the house. Its also very light on your broadband allowance.
Should you be near to upgrade with your current company maybe say you are only willing to upgrade if they throw in a Sure Signal for free.
The idea of getting a PAYG SIM for another company to test their coverage is a good one before you make the same mistake and tie yourself into another 18/24 months contract.
Take a look at everything everywhere as they are offering 4G
in key cities with some very attractive call and texts plans. In all other areas you will benefit from 3G
on T Mobile and Orange networks.