OK, thanks, I appreciate your response. I've got Optima on the way back (cheaper than basic for that flight bizarrely). I find their exit row prices a little extortionate as personally I don't really get much out of them, especially if there's any chance of having a normal seat with an empty one next to me which I find far preferable. So I guess I'll wait till the day and see how the flight looks and how the system works. Cheers!