Commuter bikes come in a range of different shapes and sizes, because ultimately, there are so many different types of commuters out there. If you're looking to take a train to work and need a folding bike to take along with you, then a Brompton is arguably going to be your best bet. However, if your commute takes you on some gravel and single track then a bike from Kinesis or Genesis may suit better. Alternatively, if you simply need to carry a lot of stuff through the city and you just need a straight forward hybrid bike with pannier compatibility, then a Specialized Sirrus or Trek FX 2 might be the answer.