I didn't get the 3G version I just tether from my iphone 4.
Similar here, three unlimited data and whatnot with my MBP and 4s linked for internet on both.

I didn't get the 3G version I just tether from my iphone 4.
You can get the Three 3GB SIMs for £8-9 at auction. They're valid for 3 months (assuming you don't use more than 1GB a month, which I'd say is enough for light usage).
That's less than £3 a month. I think you'd struggle to beat that for value!
I didn't get the 3G version I just tether from my iphone 4.
I went for three's "SIM only Internet" then used a SIM cutter to create a micro SIM that would fit in my iPad. That way you get 2gb and only £5 a month
http://threestore.three.co.uk/simonly.aspx
Has anyone tried the "3" Sim Only 1 month rolling plan for £5.11 with a 2GB allowance, cut the SIM down and put in IPAD?