i am gonna`say a shee, because if the kids don't ride you can max that sh*t out, you can get over 100hp out of the shee motor, in the dunes the shee kicks ass, all are good thoughts, althought the suspension is sh*t on the shee, and they are expensive, but it would be a fun build imo go with a shee or a 250, either way you will get to spend time with your kids and have fun doing it! and thats all that matters, i wish i had that when i was younger, it was always learning to do itm myself with my bros and friends