Depends on your commute and your conditioning somewhat. For someone like me (old, out of shape) I can max spin at my lower cadence on my mountain bike easily on the flat. But in my old commute there were too few opportunities to stay in top gear and top speed for it to make that much difference in trip time. If you are street riding by all means lock out or stiffen up your front fork and switch to some street slicks or lower weight shallow tread tires. I put Conti Top Contacts on mine, feels much more responsive. Myself I'd do those two things and then start commuting telling myself that if I put in so may days of commuting I'd reward myself with a nice new hybrid.