£15 Sim only deal with "Unlimited Internet" but it wasn't
I got 3 because (having tried all the networks with PAYG 1st..) where I spend [wife's house in Ascot] most time, a notorious mobile bad-spot, 3 was the best for 3G speed & signal strength... Other fine network providers in other locations will give different results...
As to speed I get about 1Mb at home (Ascot), have seen 3.9Gb (Waitrose car park, Wokingham..) but coverage is patchy..
IMHO all network providers lie & mislead about speed, coverage & the quality & ability of their support staff...
I could of course be mistaken: Feel free to quote me..