Unless you've driven cars with both types, you have no clue.
You've reached a wrong conclusion about Wilwoods, Sierras and Colemans. Based on what experience are you being 'psyched' on?
I've street driven my car extensively and most trips included 120MPH blasts and stops. Not to mention track use. You can never have too much brake. Your street driving will be always be 60MPH? And the big brake option is an extravagance when you're spending $60K??
Your car isn't even delivered yet and you're making judgements on performance items. If your usage is truly street biased, why are you specing 600HP??
I built and rebuilt my car 2 1/2 times over 27 YEARS of ownership of the same car. Tried every iteration and improvement ERA and the aftermarket provided-and 'tested' them all-every time out in the car.
The small brake is fine for a soft 302 car. There's no excuse against big brake for an engine combination as you want-regardless of usage.
And when it's time to move on and sell, buyers don't flock to a Camaro-brake ERA with a 'big' motor. You're putting a crimp in your value content.