I am wanting, to upgrade to the GP4-RS calipers on my R1M. I'm currently running corsacota RS19 master with the Brembo hpk rotors, stock calipers with Vesrah pads. I'm loving it. But would really like some Brembo. Seems like GP4-RS are a good bang for the buck? Any input would be appreciated. Trackonly bike. I removed my ABS.