JRitt, I understand where you're coming from for the most part, but couldn't some of those potential issues be remedied with a larger bore brake master cylinder (from an STi perhaps) and an adjustable proportioning valve? I still see the potential for ABS issues with this, I know.
Apparently GReddy did this "upgrade" on their FR-S, with separate rear calipers for hydraulic e-brake. How would they bleed the calipers if the bleeder screws were at the bottom of the caliper - pressure bleeder? Considering they're running these brakes on their 600hp drift FR-S, I'm inclined to believe they work - at least somewhat! I sent them a Facebook message asking if they could shed some light on the subject.
Again, I still find the '06-07 WRX calipers to be a more attractive option, but no doubt a lot of people will want to try the Brembos, and it would be nice to get all the facts straight for them.
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Current: 2005 Porsche 911 Carrera S 6MT
Previous: 2 BRZ's, 997 C2S, C5 RS6, C4 S6, B8 S4, GDB STi, S30 240Z, FC3S RX-7 TII, AW11/SW20 MR2, E30 318is/325i, etc.