I love Optimum Power Clean and their leather protectant. I have Optimum Car Wash and No Rinse on the way and am sure I will be pleased with them as well.
Blasting and Brembo brakes shouldn't be even remotely comparable. For basic single coat jobs I clean, outgas, blast and coat calipers for $200 give or take.
Besides a strong degreaser and Iron-X you are probably looking at blasting or recoating. Either of which will require disassembly for obvious reasons. I do a lot of calipers for my powder coating...
Thanks, it is a fun car. Like every Subaru it is "Stage 2"
Fun little daily driver, it gets raced in about every way imaginable; Auto-X, Drag, Rally and is still...
I have used Iron-X & Tar-X with great success. Spray it on, let it dwell for a few minutes and then rinse off. A little goes a long way and can also be reapplied if needed in trouble spots.
The clay change has been around for a while. It also does a great job of rendering the clay refill kit that Meguiar's also sells obsolete, since the new kit is a better value.