In a few weeks, i'll be visiting the UK and will have meetings in central london for two days, and then visits to daventry, nottingham, and northampton. i was thinking that for the meetings in central london, i can just take the underground. after my second meeting in london, i can ride the underground back to LHR and rent a car for my following meetings. does that sound like a reasonable way to get around? or should i try to travel by public bus to the other towns?