[coolhandcountry]

I think the difference in runtime is play area. I have alot of open area around me. alot of speed. It is not unusaul for me to get me truck to full speed every time I pull the trigger. The 9xl is the longest I have gotten out of a set of batteries. The only other thing close is the 14L I had. It was about the same. Just like the power of the 9xl better. 12-14 cells will flip my truck. I have to have it on grass to get maximum traction. It just spins on concrete and such. I think you will be happy with all of the above. I just putting options out there. If all else fail split the difference with a 8xl. I have not tried one so. I will curious to what you get as well.