We ran a 1LE-based Gen-4 Firebird with a supercharged AFR-headed 383 LT1 (490 RWHP) for 5 seasons and 25,000 One Lap miles on the Australian rear axle, before it finally broke. NO R-compound or DR-type tires and about 25 TOTAL 1/4-mile runs. It was then upgraded to a Chev 12-bolt (lighter and less friction loss than a Ford 9").
The 1LE carrier and axles are stronger than the old Aussie log axle...but it is NOT as robust (or heavy) as the ZL1 set-up, which must handle almost 20% more torque than the Z06-tuned LS7.
AGAIN...when GM refers to "Z/28 track performance", they are SPECIFICALLY speaking about road course action (without static or Le Mans-type starts!).
Will a Z/28 acquaint itself well at the strip? Probably...but that is NOT its intended environment...