The easiest way to explain it, is that you won't notice it's there.
You'll simply notice that everything else you drive from now onwards, has an epic lack of grip!
Unlike more savage types of diff, the quaife is fairly soft in it's operation, you won't get the inside front wheel spinning up when you plant it off a roundabout any more
Flooring it nice and early on the exit will now pull you into the bend rather than spin the wheels and understeer you away from the apex, it's truly awesome.
be VERY careful in the wet though, you'll have more grip in a straight line, and will still be quicker point to point, but when the wheels DO spin, it'll be both of them, so you'll have absolutely NO steering control at all.
First time I drove mine in the wet and the diff locked on a roundabout under power, I **** myself as the car just went straight on!
Once you're straight and true though you can pin it and you won't just sit there spinning.
