Over the last couple of days Abbey have fitted the new Kazz Diff along with stiffer Whiteline poly bushes and my God what a difference a locking diff makes, it totally transforms the rear end grip and can feel it push out of corners, It is so much more effective at putting the power down vs the stock VLSD, it really bears no comparison. VLSD is a paperweight by comparison, and one that over time, gets progressively worse and worse (and it doesnt start out with all that much lockup in the first place).
Not cheap but so so worth it !