Yes I do have cross-drilled on the 300E, front and rear. I hate to say it but I don't know the brand. I will have to dig and see.
I have over 30k on them including some heavy use this past summer. They are great and no cracking. No fade and incredible in wet weather.
When I worked for Porsche in the 70's and then again in the 80's the cracking problem rarely appeared. I agree with you, it is a question of quality of the metal and how they were drilled (as well as the chamfer cuts).
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)