I am a big believer in scopes for double rifles.
There is no reason why a "red dot" sight would not work. It would be especially good on 450 and up doubles as there is no way it can hi9t you in the face. I would have it mounted as low as possible in claw mounts.

I talked to the Zeiss people at the DSC and he assured me their Z Point it would take the recoil of a 470.

It works off of a Solar cell in daylight and used a battery when necessary.

I have been shooting one on a Blaser R 93.

The Blaser Hit Pro made by S&B would also be a good choice.