What do you mean kick out, like its going to bounce? Ive been thinking about getting one but not sure, you have to leave the rear seat down correct? or out?Yes there is a huge difference, my rear end feels like it wants to kick out alot of the time it really makes the car stiff, i didnt notice until i auto x'ed the car and it was super stiff compared to doing it with a strut bar. And, i only have 3 of the 4 optional bars