Here are some considerations and observations. I won't belabor most of the info already posted.
There will be fans of both versions. Most people will go MMR over MM because it's much newer. Newer means much lower plays and for most people newer also means more reliable. People can and have been discussing the reliability details here (and over and over, as well as in all types of iterations such as bally vs stern, SAM vs Spike, etc), but I'd just point out that newer tech evolves because it generally tends to be as reliable if not more reliable than older tech; and that general idea is what people tend to believe, understand and to go with, and they don't deep dive analyse it (even if the details may bear other considerations).
It's the purists that will seek out MM and Pinside has far more purists than the general buying public. IMO, 8 out of 10 people will prefer MMR over MM if not 9 out of 10. And that will also similarly mean that a used MMR will have a much bigger buying market than MM. You already see it with some here complaining about the high prices of used MMRs; it's a sign that the used MMR market is large and in demand, which is great for MMR owners and a potential consideration.
The new MMRs tend to be the HUO generation while MMs were most often routed. That means there is a big difference in the number of plays. And there are some very high wear areas on MM/MMR; just look at the cliffy/mantis protectors and their pictures of those areas. PF holes tend to get hammered hard on MM and MMR in multiple spots. And the mod market (cliffy and mantis, etc) has developed some great pf protection and armor to alleviate that wear from observing 20 years of use. So a new armored MMR is going to be very well protected against typical significant wear vs an unarmored MMR, and especially compared to most old MM's which already have that wear from 20 years of use. In my experience armored MMR > regular MMR > MM (outside of the megabuck restores), and we tend to observe that on the resale market as well as it's not rocket science (i.e., the newer, lower play and better condition the pin, the higher the resale price).
There are now >2k MMRs out in the wild and very few posts about reliability issues, which I find notable and useful information. And many break downs have generally been parts that are actually shared between MMR and MM.
I have an armored MMR and it's great and I can attest from experience that it looks and plays awesome. The flipper timing differences are not significant to me as an owner. I find that I am able to play MMR without any significant flipper/gameplay timing differences/issues and including when compared directly side by side to my other Bally/Williams and Stern pins. And for many/most I'd expect it to not even be noticeable (though I'm not surprised some of the best players in the world observe a difference, you don't get to be an excellent player without being very good at details). OTOH, I have played a HP FT and the flipper timing and game play differences were/are significant, to the point that I really struggle with playing it on route. So I do know about and understand flipper timing differences.
Take MMR with it being new or low play and add in the integrated shaker and high res color dmd options and it really is a great pin preferred by most people. Many MM owners happily sold and bought MMRs when you read the internet history.
I've tried to talk about observations and not be blindly subjective. Again, both versions (MM and MMR) have their fans. The typical #1 rated pin, and I see why so many love it.
. And that pin is so rare in my area that it may be easiest/best to get it new.
; there are top 20 rated PS pins with over 10X more reviews than on IPDB.
Northfield, MN
Saint John, NB
