I appreciate that. What has been said pretty much confirms what I had thought. I was looking to see if anyone had a strong reason to avoid the Z/28. My motivation is purely an illogical one to have both the gm and ford versions of what I think will be the last versions of the unique naturally aspirated manual pony cars.
He's an older guy. He pretty much decided the cars were relatively close in raw performance capability, but that the GT350 was able to do it with much less suspension drama. He's always complained that his Z28 beat him up on the street. (They weren't available with anything like Magneride) He pulled the trigger on a trailer setup this year so he could get to track events without a Chiropractor visit.
As for reliability, it's no different than a GT350, in that there are always common problems to be solved. In his case, it was punting the stock carbon ceramic brakes for iron discs, and upgrading the crank pulley to one that won't delaminate.
I don't think he'd be able to come up with a strong reason to avoid one, other than maybe possible parts availability problems. They didn't make very many.