[Sauce]

Originally Posted by attila

First of, I am not a professional driver by any means. Never raced, but love driving on a track. So things can be very different for a better driver.
I tracked the M3 for two years ( about 18 track days) this is my second year with the RS but unfortunately, due to work this year, i did only 3 track days so far.
The RS is unquestionably faster than the M3. On the other hand you are not out there to "win". Both cars are predictable but in a different way. (I run both of them on BFG-R1 tires.) The M3 tends to have more understeer on turn in even up to the apex sometimes (if you carry to much speed in) then can be easily corrected by throttle. So much so, that power oversteer is the main threat upon exit. This oversteer is progressive and relatively easy to capture. (depending on tires, with the BFG-R1 you have to be way more careful than on OEM) Upon exit the M3 has some difficulty to put all the power down. The power delivery of the M3 is more linear than the RS and easier to modulate. The RS tends to start the turn in with less but still present understeer which is very easy to address. Minimal lift off and you are right on your target slip angle! Actually this is one of the most lovable feature of the RS. Then after you corrected the understeer you can get back safely on the throttle way earlier than in the M3. I start to put down my right foot even before the apex. Throttle acts like a glue on the rear. (well within certain limits of course) One issue, the regular GT3 and RS as well tends to have a really weak LSD way worse than the M3 so sometimes that's the limitation to put down the power. (also gives you lots of ass wiggling under breaking)
(this, the LSD and the weak rear toe links need to be corrected on the GT3's)
Both car fun on the track. Initially I felt more exhausted after driving the RS than the M3, but now it's not so bad. For drifting I use my wife MX-5 in the rain. No people out, thin tires, OK LSD, you can drift at low speed, and not wreck an expensive car. Drifting is fun, I use my heatcycled tires for drifting before I got new ones. Well I should say try. Getting better but still 1 in every 3-4 drift I end up in the wrong direction, so I get black flagged.
Lots of people wrote quite a bit on these cars how they drive etc. Bottom line is both can be fun, and both needs some mods to be track ready.

Absolutely, LSD's on GT3's need to be treated as a wear item. When the ass starts to wiggle under braking and you do the "diff test" and you don't feel much resistance it's time to call guard. Letting off the throttle can rotate the car hugely, and when throttle is applied it feels like the car is rotating on the axis of the two rear tires. I LOVE hearing/talking to GT3 owners such as yourself, it needs to be experienced to understand.