Sorry I may have been mistaken about there being room for 3 but I do remember some of the driver's making us transfer to a seat but then after we moved and others boarded the bus people would sit their kids or themselves on our ECV's and the driver never said a word to them then about safety!! And then later into our trip we had other drivers that told us not to transfer to a seat but to sit on the ECV's and then provided us with a seat belt that he had attached to the tie downs. Which we were glad to use so that we did not get some of those evil looks from the other guest about boarding before them and the comments about taking up the extra room with the ECV's. Everything depends on your drivers and we were always given help either driving them on to the buses or after getting them on as the driver's would maneuver them where and how they wanted them parked. Some drivers wanted us to back them up the ramp, some to drive them up, but we did get Lot's of help. Maybe cause I was new to using one and some times had a bit of a problem driving them on >> or word got out that I almost ran a driver over LOL
And as far as tipping over we never had any problem's with them on the buses or off in the parks. LouigiAnne