Still curious as to how much better a set of TTRS calipers with 340mm disc really is over the NQSBBK, but when you run the 2 piece 370mm brakes its obvious. I'd doubt I'd find d the limit of the NQSBBK, let alone your setup!
I had the NQSBBK on my Golf and they were fantastic when combined with Ferodo pads! Perfectly suited to the 312 disc on a Golf.
I've got the 340mm TTRS on the CC and they are ultimately a better brake but they are heavier and my opinion offer less feel than the NQSBBK.
That said, they're perfect for the bigger discs and my bigger car.
After upgrading the brakes on my last 2 cars, the extra confidence they bring, control and modulation.........I have no idea how I will run standard brakes again.