Are Vodaphone, T-Mobile and Talk Mobile good mobile service providers? Which is best?

Hi,

I'm used to Three network. I've found their service extremely good over the last few years and I finally may be switching service providers because of the phone I want (Nokia 5530).

I can only get this phone on either Vodaphone, Talk Mobile and T-Mobile. I'm a bit wary on changing service providers and so want to ask which one you guys think is the best one, in terms of coverage and general service really.

This is the phone, showing the three providers with the same price btw (£15 a month):
http://www.carphonewarehouse.com/mobiles/choose-tariff/NOKIA-5530-XPRESSMUSIC/MONTHLY/NEW

Thanks in advance guys