MONO cartridge recommendation

Salectric, If your mono LP is truly pristine, I don’t suppose you would have a particular problem with noise due to surface wear, but the point was and is that on mono LPs, the audio signal is encoded only via lateral deflections of the stylus. Any vertical deflection of the stylus will induce surface noise and no music. The point about a true mono cartridge is that such cartridges produce no signal in response to vertical deflections. Many such cartridges, in fact, have no vertical compliance. Ergo, playing a mono LP with a mono cartridge is very likely to result in less noise due to surface irregularities than playing the same LP with a stereo cartridge. This is just a fact, not subject to opinion. With a mono cartridge derived from a stereo cartridge by internal bridging or if you use a mono switch on your preamplifier, the noise due to vertical deflection of the cantilever is also cancelled via the summing of the two channels. However most of the latter type mono cartridges do have vertical compliance and some of those do respond to vertical motion of the stylus; it’s just cancelled later in the pathway. (In some cases, mono cartridges derived from stereo are built such that there are no coils or magnets to transduce vertical motion of the stylus, in which case the cartridge cannot respond to vertical with signal voltage output.)

I mentioned that I played mono LPs with stereo cartridges for decades with no thought to this issue. So, I certainly never said that such a practice is "too noisy". I did say that now that I am cognizant of these issues and use a mono switch where I have one, there is a very obvious improvement in signal to surface noise ratio and in addition in other areas of reproduction. Mono LPs that I heretofore have avoided due to what I thought were noisy surfaces sound much much better even in feaux mono (using a mono switch). 

Sorry. I am sure you know all this stuff, and I see that you are way ahead of me in already owning a Premium Be Mono.  That's the one I want.

Very good information.  Thanks guys!

For the OP, the only recommendations in this thread that will really work for him in terms of the gain and his phono preamp, without getting into complications with a step up, are the Ortofon 2M Mono SE (from Thakker on Ebay) or the Denon 102. 

If I was forced to choose between those I'd definitely opt for the Ortofon as it offers a better stylus (although much more critical of setup) and does not have the restricted frequency range of the Denon, which is a bit off-putting for me. 

I'm currently using a rebuilt Ortofon MC 20 Super (boron cantilever & microridge stylus) strapped in parallel for mono (no mono switch here) and it sounds very good, but am going to experiment a bit with it soon wired in series instead as I have slightly quirky phono stage (current mode as opposed to voltage mode). 

I'm a cheapskate, so if I was to pop for a mono cartridge, pretty sure that I would do the AT 33 Mono, run it for 400-500 hours and then retip it with a very good (boron or sapphire) cantilever and microridge or line contact stylus. I bet that would be an absolutely killer mono cartridge for about $700 all in and give some of the very pricey mono cartridges a run for their money. Unfortunately that won't work for the OP with his phono gain. 

My experience mirrors Folkfreak’s.

Miyajima Zero sounds very good indeed, almost as good on pristine mono as a higher end stereo Koetsu. Without an immediate A-B comparison, one would not hear a difference. On worn mono vinyl the Zero is clearly superior.