I have the aluminum split mount. Definitely did not "need it" per say - but I am only running 4S. I think overall it is pretty good. Initially, I ran into a little challenge with what seemed to be some extra unwanted side to side play in the center diff. Now, I was also adding in the M2C aluminum center diff at the same time (never a good idea to change two things at once, which is what I did !). Long story short, I found that if I just assembled the split center diff housing per the steps in the instructions, tightening screws per the manual's steps, then things snugged up and aligned properly with no extra unwanted side to side play in the split diff housing. originally I thought it was a bad mold or something on the upgraded aluminum diff housing - but in the end, just put it all together nice and slow and methodical.