As an owner of both, think the Z/28 is slower for the fact that it is 145Hp less then the ZL1LE, and cost more as it came with Carbon ceramic brakes that's a $6K+ hit.
To date i like the fell of the Z/28 brakes better then the ZL1LE, they both work well, the Z/28 has more of a bite when you step on the pedal, i know there good brakes on the new car,(we have tested them)
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