Having only had the stock Cervelo re-branded brake calipers on my P2, I’m wondering if there would be any noticeable difference in braking power going to Ultegra? I’m considering replacing the rear caliper with Ultegra (or similar price-range options) and saving up for a Tri Rig in the front later. I have Cane Creek carbon 200tt levers, fwiw.
I find the Shimano ones feel and work much better. The stock ones are certainly passable but if you want an upgrade do it.
You might want to try simply changing the brake pads first. I found the Kool Stop salmon pads to be far superior than most stock pads (and < $10).
-Scott
Agree about the kool stop salmons. Huge increase in performance on any brake (for AL braking surfaces). Even if you later upgrade the whole brakeset, save the kool-stops and put 'em in your new brakes.