I don't know anything about the CompBrake stuff but i have just fitted refurbished calipers due to suffering, probably for years, from the corrosion under the pad guide problem and the improvement in braking performance now that they are working properly is phenomenal. I can't imagine wanting to upgrade them now, although admittedly I will only use it on the road whereas you might do some track stuff. I think there is a huge amount of hype around the benefits of upgraded pads and discs. I just got standard discs from buypartsby and standard Pagid pads which were on offer. The calipers had been fully refurbished by a member on here but then not used. Autolusso do them though and they should be good. The result is eyeopening and presumably a lot cheaper than the upgrades!