It's definitely slower, but factoring it all in real-time door-to-door - there's only a 35 minute difference between me and the train journey (33 miles). I ride to the station, wait around until the train gets in, get on and wait for it to leave, then ride from the train to my office. On my own, I just ride - so if you don't count all the waiting around with the train, the train is a LOT faster - I just don't like to cut things close with train timetables

7:55am->10:15am (bike) vs. 8:30am->10:15 (bike & train).