For people working in the downtown Toronto core, the commute into Union Station is a huge factor when deciding on a place to call home. The GO Train is a solid option to commute from further away suburbs. Some use the commuting time to sleep, while others use it do get a head start on the work day. There are a few stations so close to Union that the train ride could be as short as 15 minutes. Farther GO Stations are supplemented with express service trains at certain times to faciliate shorter travel times.
Here's a breakdown of the current GO Train lines as of January 2019 and their commute times.