Terry,
Interesting! I, like you, have used several different brake pad compounds searching for that "magic bullet" compound mix... While I haven't strayed beyond the Carbotech and Hawk lines, my experiences were completely different than what you found. Bottom line for me was that the Hawk DTC series was the "best bang for the buck" overall, although I did prefer the bite and release characteristics of the Carbotech XP series by a small margin. My big problem with the XP was that it just wore far too quickly. My experiences showed that the XP was VERY "rotor-friendly," but it seemed that they were engineered to sacrifice the pad material in favor of low rotor wear. The Hawk DTC series, though, lasted considerably longer, although with an increase in both rotor wear and metal content in the brake dust. In the end, I wound up doing a cost analysis and it basically boiled down to lower season-long expense to replace the rotors a bit more frequently and the pads less frequently.
Also, unlike you, I found the best brake balance with split compounds (XP12/10 or DTC-60/HT-10) with the stock 13" PBR setup, and square compounds (DTC-60) with the 14" Brembo setup. I'm wondering if some of the differences in our experiences are in braking or driving style as well as chassis weight. I will admit, I don't make anywhere NEAR the power levels you do (313rwhp), although I do carry similar weights (started at 3719, as low as 3250, currently 3308, all with driver and fuel). Also, I've never experienced "ice mode" in my 2006. Given the difference between the PCMs in the 4.6 and 5.0 cars, I'm wondering if there's some interaction in the DSC programming that accounts for that.
As for having the Hawks come apart, I've only seen that once, and not on my car. Last September, I put fresh DTC-60 pads on the car front and rear, and then: Hit a random track day for shakedown, four 20-minute sessions. Ran an Enduro (5hrs total track time, 30 minute practics, 4.5 hours race-time), 20 minute practice and 10 minute qual sessions the following day, plus a 40-minute and 20-minute sprint race plus two TT sessions. On Sunday ran a 20-minute practice, a 20-minute sprint, and a 10-minute TT session, before the pads finally wore enough to allow excess heat transfer, boiling the fluid in the calipers. Essentially, that equates to 540 minutes of "advanced level" driving, call it 9 hours total time on the set.
Now, I will grant that the Enduro pacing wasn't as hard on the brakes as the sprint stuff was, but we (3-driver team) were still driving it pretty hard, and essentially non-stop for literally HOURS on end. Also, while we didn't do temps for that race, I have seen numbers as high as 1200*F (~650*C) pulling into pit lane after repeated hard laps, so I don't think it's a case of "pussy footing" around on the whoa pedal. Also, FWIW, in the Enduro there were two in-class cars that did consistently out-brake me, but both retired prior to the end of the race, one with a cracked caliper...
Overall, I'm pretty happy with the DTC-60. I could wish for a bit more initial bite, and as you have observed, the release isn't 100% linear through the temp range, but they handle the heat and, last long enough to do some serious racing. The only time that I feel like I'm running too much rear pad is when trail-braking with a very low fuel load, the tail gets a tick unstable. I've had a couple of people recommend the PF-01 to try. Do you have any thoughts on that compound, how the behaviour compares to the Hawk or Carbotech lines?