The rear sight on the SRH comes off easily. However I like the fact that the Burris mount allows you to retain the rear sight. That way if there's a problem with the red dot you can remove it and still function with the iron sights as your backup.
In my case, it's not so important. With age my eyes can't focus on the foresight without special glasses. Fine for target shooting but no good for hunting when you need to see the game not just objects at arms-length distance.