Rifle sights are great if your eyes will work with them. IMHO they are miles ahead of a bead when shooting slugs although there are are many good folks who can get good results with just a bead. If you decide to install a ghost ring rear sight, you can use the front sight that is on your rifle sighted barrel. You can just remove the rear sight blade or for a bit more money you can have the rear base removed and the barrel refinished.
The standard Remington rifle sights leave something to be desired, but there are some very good aftermarket sights available.
As a side note. I had a customer who's eyesight is so bad that he can't shoot with ghost ring sights. He bought an 18" rifle sighted barrel and I put a set of Ashley Outdoors express sights on it. He can see that 1/8" tritium bead.