Yes, I have dual setups on my turntable with one being a dedicated Ortofon mono cartridge. On the superficial side, yes, you'll find that many mono records will play with less surface noise than via a stereo cart. My experience is that dedicated mono cart >>> stereo cart + mono button >>> stereo cart. I spun my original of Bill English on Vanguard the other night and decided to compare carts (I just replaced both carts two weeks ago). The mono was huge, in your face, jumping out of the speakers, sound. The stereo seemed like someone was playing it through a cheerleader's megaphone.... from the other side of the gym.
Happy Birthday! I hit the same milestone and treated myself to a new phono stage!