My Argument for the C8 Z06 over the C8 ZR1/ZR1x
Before I even start I actually own a C8 Z06 and I don't own a ZR1 or ZR1x, so I guess that makes me partial. Anyways, here you go:
The C8 Z06 is the most powerful production N/A V8 engine and there is no reason to believe this will ever change in the future.
This one is highly subjective but the Z06 has the nicest exhaust note out of the entire C8 line of cars.
The C8 Z06 is much more practical for daily use simply because it has a front storage compartment. Yes, the rear trunk has a decent enough size but you have to take care not to put your ice cream from the grocery store back there because you may find it liquid by the time you get it home.
The price. This point wouldn't be so much of a sticking point if you could actually get the ZR1x or even the ZR1 for MSRP. You can't, but you sure can get the Z06 for a good bit under MSRP.
I'm sure I missed a good point so I will leave number 5 for you guys in the comments.