Mono Cartridge, is it worth the investment?

I am using the Graham phantom with one arm stereo Jan allaerts Finish and another with Lyra Helikon Mono cartridge. Swapping arms takes me 3 minutes.
Sound benefit with the mono cartridge is huge with records pressed before1960. On recent reissues of old mono records is less audible. So if you have original records mono they deserve a good mono cartridge, you will be surprised how good they sound.

Slowhand, if you have a VPI tonearm system it is even easier to swap armwands,all the settings are done only one time, so it takes 30 seconds to swap arms !

Slowhand - I appreciate your developing interest...I'm noticing the same thing as I get back into Lps. Those old 50's mono records sometimes sound really nice. But what a pain to collect! Finding them in decent condition, cleaning them, etc., and the results are all over the place. But some of the old Ansermet, Monteux, Toscanini...fun stuff! A mono cartridge is on my list, but I don't see how I can do it simply without a 2nd turntable, for which I don't have room. In support of Jloveys' comments, however, I've certainly heard from the "old hands" that mono cartridges help those old mono records sing!

I give an example: Miles Davis "Round About Midnight", Mono 1957 pressing "six eye" deep groove CL 949 . Record in VG condition, in not so good state.
Played with a top stereo cartridge you have a constricted dynamic range, a high background noise, ticks and pops. Same record with same system but with top mono cartridge : Big soundstage, Dynamics to die for and ABSOLUTELY QUIET (just some very little audible ticks from time to time).
So if you speek investment, if you buy a top flight MONO cartridge, you save alot because you can hunt for old mono records for cheap and enjoy them much more than those fake stereo reissues. Those are great sounding and musical records not to miss if you like jazz.

Another thing, playng a true mono record with a stereo cartridge with phonopreamp and amp switches on mono is a little better than stereo switch but NOTHING to compare with true mono cartridge.