Ye olde mobileshop.com is currently offering the Samsung Galaxy S III in Marble White for £21PM on a 24-month contract. That works out at £504 over the two years; almost certainly cheaper than the SIM free + SIM only route.
There are various T-Mobile allowances on offer. Behold:
- 300 minutes, 250MB data, unlimited texts
- 100 minutes, 750MB data, unlimited texts
- 50 minutes, 1.5GB data, 250 texts
Free next-working-day delivery.
(Thanks to scottydoobuy at HUKD)