There really is no clear answer to this question, because it boils down to a personal preference. Riders typically like bike seats because the child is right next to their driver and the driver is able to gauge and monitor their child more closely than in a covered trailer that is separate from the bike. Furthermore, a trailer takes up more of the trail and is it almost impossible to maneuver with a trailer in tow. Trailers also limit the types of trails that you can scale. With a kids bike seat, the driver still have virtually the same footprint on the trails as if they didn’t have an extra seat, and they are able to scale any type of terrain that they feel safe taking their little one.