|to start I'm not trying to change anyone's opinion on them. I also grew up on the Ziptied forum and Zilva fourms of the day and VLSDs and ATB got a lot of hate so that may have something to do with my opinion 20 years later.
I don't like Quaifes for a RWD for a variety of reasons.
I started off drifting in 05 and did it until 2015. I don't anymore but I do enjoy going out once in a while and having a good time and even if a Quaife will allow me to get sideways for a moment I dont think it would be consistent enough to make me comfortable.
They also seem, to me, and feel free to correct me Quaife owners, like a glorified open diff. Where if you are driving in adverse conditions and one wheel starts to slip it will send all the power there vs keeping the non-slipping wheel under power also. Or if you angle up a steep driveway and your low/stiff car has a tire lift then all the power goes there and are stuck.
Again, most of my issues with them are on a RWD chassis. I would totally install one on a CTR or Focus ST.
Most manufacturers dont use them and thats saying something since they are cheaper to build and easier to maintain and etc etc etc.
The new Z for instance is using a clutch-type LSD and im sure this is for a reason. Switching from the S-chassis community, which ive owned 7 or more, to the Z32 community its crazy to me how many people ive seen say "OH stick with the VLSD its the best!" and that's only a slight hyperbole. I just dont think Z guys track their cars as much or dont appreciate what a good LSD really can do for the driving characteristics. Hope this doesnt come off like a rant and im always open for discussion!