NCPM, I had 3 of my 4 Pirelli PZeros develop cracks after only 4 years. My 2014 R8 only had 6,000 miles at the time and the car is a garage queen. Switched to PS4S and they are so much better! I have a long relationship with the tire store that sold me the Michelins and they sent the 4 Pirelli tires (that came with the car new) back to Pirelli for inspection and Pirelli gave the tire store $624 which they passed on back to me. I had been a loyal Pirelli fan since the 1990's but now have Michelins on all 3 of my cars as the last set of Pirellis on each of my cars has been disappointing. Seems like Pirelli is not the same quality tire it used to be.
To Helldriver and Scott-Ahlmann, my Audi dealer recommends 40 front and 38 rear as my car mainly sees road and highway use below 100mph. I've had psi set to 45/41 factory specs before and the front seems to be too light/bouncy to the point that I feel that traction is compromised. Is this normal?
Sorry never really answered your question about the higher pressures. The ride is significantly better at the lower pressures so in any real bumps the car does not feel good at the 45/41...for me even in normal mode. But sport mode through the bumps is not good for me at either pressures and is actually worse.
So I can see why you feel the front end too light and bouncy at the 45/41 and mid or below speeds if there are any real bumps.
The steering torque ("weight") feels lighter than too at higher pressures so that may also be adding to this sensation for you.