i've had alot of seat time in my shops Boss 302 daily driving it the last two months. It's a good car but it is not a vette. Versus the c6 Z06 it's not even comparable at all. Versus my old 2007 LS2 Z51 i still think the vette is better in every way once the tires are changed. The boss has better brakes but carry's too much weight to be better at braking. The suspension is better on the C6 and the light weight amplifies that. As far as modibility the LS2/3 vette can get close to 130 trap speed without power adder or short block modifications. The mustang just isn't getting their without boost it's just too heavy.
Coyote/Boss has been trapping 122-123 with just bolt-ons, they can definitely get close to 130 with cams/heads. But of course, that likely entails spinning 8k, buying a high rpm competition pulse ring and you gotta throw in billet oil pump gears and valve springs to be safe, also probably a radiator & oil cooler if it's not a Boss already. I know I would if it were my build. But still, 600 flywheel hp all motor is a really nice number coming from five liters of disaplacement with bolties and some top-end work.