OP - Congrats on a clean done up 991
I did the same thing. .. Got out of my Lime Rock Park ///M3 6spd and got a 991 C4S Cab 7spd.
Just like the OP said - power delivery is very similar but I have every option and the PSE deffinetly makes a huge difference in the sound - I it drive with it on...I especially love the back fire burble...very intoxicating....
I too am curious about the New ///M4 Cab