It is important that you choose mobility scooters that fit your lifestyle, abilities and plans. The most obvious difference between mobility scooters is whether they have 3 wheels or 4 wheels, but the difference is more than just looks. 4 wheeled scooter are most reliable when it comes to outdoor use on rough, uneven terrain. Two wheels in front and back make for a stable ride.Turning radius is not as tight as most 3-wheel power scooters and may not allow you to maneuver as well within the home or in crowded areas. Typically wider and therefore less likely to fit down narrow hallways and tight spaces