ive been with them 10 years +, im a fan.
as with all networks, they have fans and haters, ive had a few issues, but all networks have issues.
You could allways pick up a free pay as you go sim, stick it in a spare phone and see what the signals like for you in your normall locations? As with most networks
http://www.t-mobile.co.uk/shop/free-...ef=main_panel1