All of them that I've every seen - except the real cheapies - are Fisher Price Power Wheels. For our 2 kids they have a 4 wheeler, a rail buggy/terminator type vehicle, and my personal favorite the Silverado. The four wheeler seems to be their favorite. Easier to get on/off vs. in/out. The handle bars also make it easier to steer vs. the car/truck w/ steering wheels (no power steering /forums/images/graemlins/laugh.gif). They do ride on the 4 wheeler together, but the Silverado is the only one designed for 2. It is the biggest PowerWheel they make - but that is a draw back considering they still use the same battery motor combo. It is slower and the battery doesn't last as long as the other ones. We have 4 batteries for 3 vehicles and are constantly swapping one of them out. Here are my kids riding their 4 wheeler.