I've been using them since they came out. Initially I thought the same as all others, a pain to keep consistent. But then i decided to go with the heaviest springs and fill them with diff oil. I run the front with 5k as I would a normal diff, and 5k in the center (a little softer than normal for my liking). They stay very consistent for turn-in, but give killer acceleration out of turns and into jumps with little run up. Maintenance is just like a normal diff. For those of you who have them, try using diff lube instead of the grease.