For bumps I have found the superkart chassis the best. The sprints are okay but so hard on your ribs that even with rib vest I separated ribs at Grattan a few years back when I drove the KZ sprint. The handling also feels more like laydown which is nice. A few guys are talking of putting 125s on SK chassis so you could do that too. I know you had your converted sprint chassis at one point which I know you had issues with handling but I have been very happy with my Anderson chassis.