The 156 V6 Q system is by far the best automatic I have ever driven. Out of all the possible marques and combinations of engines they are completely different.
You drive a Mercedes with a slush box and it feels like a lazy car, it isn't keen on wanting to play when you want it to.
The Q-system however transforms instantly to a beast on demand then settles to a quiet cruiser just as quick when you want it to.
Then there are the added bonuses of a sport button that sharpens throttle response and a much revvier power band. Best of all though, at the flick of a wrist you can put the gear selector into H box mode that offers manual thrills.
You do not need a Q2 diff in a Q-system at all. It's just £650+fitting wasted. !
The Aisin torque converter and box do just as good a job at offering stability out of junctions and high speed corners...
Just put your foot down, give it the beans and watch the car do exactly what you want it to do without any drama or fuss.
You also have a very clever Ice button that dumbs down the throttle, the box response and uses 2nd gear to pull away without a hint of wheel spin in the worst of conditions!
Only a month ago I took out a BMW 535 auto owner out in my Q-system... He described the response as "not normal, an automatic shouldn't be able to do that" LOL... Guess who is now wanting one? LOL
Don't take my word for it, take a Q-system for a test drive and see what I mean for yourself.