i ride every day to and from work 7 mile round trip 3 and half each way!as said u will notice to little hills etc that u never thought was there!my journey is quite hilly! takes me 10 odd minutes but the first few weeks it was horrible!!plus the wind is always against u!and the wind makes alot of difference to the effert u have to put in!!i ride a mountain bike but still got off road tryes which dont help but u will get alot fitter and saves u alot of money