SME M2-12R Cartridge Choices

I have an MP-50 that I haven't tried in that arm but I don't see why it wouldn't work, with a self-weight of 8 g and compliance of 8.5 x 10-6 cm/dyne. You might want to pick up a few aftermarket headshells of various weights for experimentation. If you want to use an arc protractor like a Mint LP, which I'd recommend, you'll need a slotted headshell, anyway.

I was thinking of something in the Nagaoka line. Any thoughts?

Don't know why this arm doesn't get more attention, especially since it's basically an upgraded version the classic 3012R, with better bearings and wiring. I've used an SPU Royal GM II and an SPU Mono GMII, both of which work wonderfully. And I recently installed Benz Wood mono with an Ortofon 2000 headshell (approx. 15 grams). I was a little concerned that a 9-gram, medium-to-high-compliance cartridge might not mate well, but no problems at all--sounds terrific. I'd imagine most cartridges would be fine. It's a flexible arm. But you should think about replacing the stock phono cable, if you haven't already. I found it edgy.