My HO - Don't get a hood.

They were used to protect and / or shade the front sight
but in reality you don't need one - better to get a front sight
that maintains the same light refraction regardless of where
the sun is shining.

A set trigger is something normally found on bolt guns where
you push the trigger forwards which "sets" it so it then only
requires a light pull to fire the gun.

I can't remember seeing one on a DR unless they are mistaking
a set trigger for the front trigger that is hinged (like on some
Holland shotguns) to stop you hitting it hard on recoil.

500 Nitro