I have looked around on all of the major network providers and none of them beat these contracts. Plus you can cancel after 30 days if you dont like it. In fact im fairly confident that these are the best out there so i challenge you to prove me wrong ;).
I think this is in store too.
Plus £35 cashback via Topcashback.co.uk or Quidco.com
If you follow the link you will see that all texts have been increased to unlimited.
Solo 15 (30 days) 350 mintues and unlimited texts
Solo 20 (30 Days) 600 Minutes and unlitmited texts Free mobile internet
Solo 25 (30 Days) 800 Minutes and unlimted texts Free mobile internet
Solo 30 (30 Days) 1400 Minutes and unlimted texts Free mobile internet
Solo 35 (30 Days) 1800 Minutes and unlimted texts Free mobile internet