If I'm not incorrect, he was the first replacement... and maybe did the entire rest of the run when Hayden left?
He has a phenomenal voice, that can certainly do the score justice beyond what even I claim Hayden did, beyond what most could do... and he is a solid actor for sure. I'd have lvoed to see him. But having seen him in many shows, I don't think he'd top Hayden in the acting dept, but I'm sure many audiences were far more thrilled seeing him in it than Hayden, given how shakey it's said Hayden could be vocally night to night.
I'd also love to have seen Marcus Lovett, and Patrick Wilson on tour, and Brian D'Arcy James who was suggested here could have been better casting for Billy but was only in the ensemble.... but it doesn't change how revelatory I find Hayden.