It is dovetailed for Novak rear sights and a high visibility front sight. Changing sights would be easy with this revolver. The barrel is a different profile, with machined flats on the sides. Probably couldn't get that machine work done by a gunsmith for much less. I don't know if Ruger did any trigger work on those, but the gunsmith back in GA that I used to go to, would do some nice trigger work on the GPs for around $80.
The other thing you have to ask yourself is if you would want those features on a GP100 if you bought a base model. If you do. Then $100 more s not a bad deal. If you would have been happy with a standard GP. Then the extra hundred isn't worth it to you.