You really haven't experienced mono until you have a dedicated cartridge...
I would love to hear more about this. What I've read over the years is that there is no electrical difference between using a mono cartridge and using a stereo cartridge with the mono switch engaged. I don't have enough knowledge of the subject to know if this is true, but here is an explanation I found in another forum:
"A stereo phono cartridge has generators that are sensitive to 45-degree motion corresponding the the 45-degree groove walls. It is wired in such a way that lateral motion of the stylus is in-phase and vertical motion of the stylus is out-of-phase. Therefore, when you blend the channels with a mono switch, purely vertical motion is completely canceled and purely lateral motion is maximized. This is exactly the way a mono cartridge operates. There is absolutely no difference whatsoever."
Personally, I prefer listening to mono records with a stereo system. After all, I bought many mono albums when all I had was a mono system with the promise on the record jacket that "played on a stereophonic machine, it gives even more brilliant true-to-life fidelity." I have found this to be true. I also like having the music centered between the speakers while what noise is present is usually off to the sides and, to me, less intrusive. For very damaged records, I also like having the option (on my preamp) to feed either the left channel only or right channel only, whichever gives cleaner sound, to both speakers.
But I'm always willing to learn and am curious what advantages people hear when changing to a dedicated mono cartridge.