I did similar upgrade, and used gsxr brembos. No complaint with the caliper. The set is much lighter than our stock brakes. Power/feel advantage? not really I'll have to explain...
The stock gsxr brembo pads were terrible. Low power, and a lack of feel.
I switched the pads out to a vesrah, and have been very happy. I also added Brembo master cylinder form a 2012 ducati 1198 sp. I was running Galfer Wave rotors, 310mm size. Great power. Huge power form the first second
Last spring, Im lookign at ebay, and someone is selling the 330mm Brembo rotors from a 2016 zx10. 150.00, including shipping. I had to have them.
In all seriousness, they do not have the grab, or the instant power of the galfer wave, but the feel is so incredibly smooth, Ive learned to really enjoy them.
What I learned is:
Goodpads are most of the battle. A good caliper, with a long wearing, consumer issued pad is nothing.
I really like the round rotor and not the wave. The round rotor feels like I have more braking range, for lack of better words. The wave grabs too hard, initially.
The gp4-rx was not available when I did mine, or thats what Id have used. I believe their quality is higher than what I have. Still, no complaints.
Good news is that after spending almost 800.00, I am sure I at least equaled my concours 14 stock brakes, and maybe even bettered them..maybe.