They made or make the stainless flat top in a 45 convertible I have a 45/8 model good shooter.
I will mention the 45 had a lot more thread choke (I fire lapped it ) than my stainless 44 special bisley 45/8. I don't know if that is typically true or not.
The governor is a neat idea but you loose quite a bit of velocity and accuracy in the long free bore of that 410 chamber.