While 1Gb is fine for most people on their phone it does start to get restrictive when you are using it on a laptop where you have far greater storage capacity. Try downloading Windows service packs or games patches for example, and you would soon go over.
I had to sign up for 18 Month with 3 for a free dongle and 5Gb a month for £7.50/ month but for my phone I am quite happy paying £20.51 (although that will come down now the VAT rate has reduced) for Flext35 and W'n'W Plus with a 3Gb FUP.
