Any particular reason you've considered that if you don't mind me asking?
It's my mother's connection, and as I'm here for month or so before uni starts up again, I'm currently burning through her 40GB rather speedily (so much Netflix..), so being able to upgrade to unlimited for the month would be rather useful. Having said that, considering at current rates we're talking about 5 days before I hit the cap, being able to upgrade immediately even if it came with a new 18 month contract, would still be better.