I picked up a hard shell RTT used that did not have a ladder. Figured I would buy a telescoping one but was wondering if the 8.5' (lighter, more compact) is good enough or should I get the 10.5' (taller) to play it safe. I am sure the 8.5 would be fine on level ground (with the slope of the ladder included) but I have had times where the gound slopes away from the truck and/or I have to put it up on some wood/rocks to level out and did not know if I would ever get into a height of more then 8.5'. The test will be mounted on an Xterra with a 2" lift so not extremely high to start. How often has anyone needed more then 8.5' of ladder?