Phono preamp worth it with MM cartridges?

@lewm  As I said 30-100k Ohm (which is from 30k to 100k). 
When you will look at the manuals for MM cartridges from the past you will see a range of recommended load from 30k to 100k. I'm not gonna say 30k is better, I prefer 100k Ohm nearly for every MM. But when the best MM cartridges were designed the loading range from the manufacturers was 30 000 - 100 000 Ohm.

Today 47k Ohm is standard, but today's MM cartridges are 95% junk.  

There are some killer MM cartridges, but not your Rega, you'd better change a cartridge first.

Some MM or MI phono cartridges are more expensive than MC.

A phono stage is important for all types of cartridges.
There are many inexpensive MM/MC phono stages on the market, the one I really like is JLTi mk4 (now mk5 available from the manufacturer).

Different loading for MM is also a very nice option, so the loading is NOT only for MC.
Loading for MM must be from 30 to 100k Ohm. A phono stage with RCA-Plug resistors for MM is nice to have, but internal resitors in the phono stage must be very high in this situation (500k Ohm) to load it down with parallel RCA-Plug resistors .

what to your ears would be a better sounding MM? My local dealer offered me the 2M Black which I’m open to as a long time fan of Ortofon but he thought it comparable to the Exact. I guess there’s no point buying a better cartridge than the deck/arm I have can do justice to?

I really wish the dealer had talked me into a getting P6 to begin with. The other option at the back of my mind is to do neither and move the Exact to a new P8 and sell the upgraded P3.

Can you adjust VTA of your tonearm to properly set up another cartridge?

There are many amazing MM cartridges, but I prefer those best from the 80’s (they are crème de la crème of MM). Depends on the budget, under $750 I always recommend Pickering XSV/4000 or cheaper XSV/3000SP. Wonderful cartridges, especially the XSV/4000 with Stereohedron stylus. If you can’t find NOS ask me! The Pioneer PC-1000 mkII is another favorite at the same price as the XSV/4000. What else? Sony XL-50 is very special for reasonable price (Boron Pipe cantilever!). And I like Grace LEVEL II but it’s very expensive!

I hope you can change Rega to Technics GR :)) 

Yeah, all you need for LOMC is sill a decent MM phono stage and external SUT to match cartridge impedance. I’ve been using this pair of SUTs and it can cover all types of LOMC (from low to high impedance).

MM stage and SUT is a classic combo.

A great MM phono stage is a must have, in my opinion great MM stage should not cost more than $1200 (many available withing this price tag).

@lewm MM cartridge manufacturers in the 80’s clearly stated 30k - 100k Ohm range for their best (top of the line MM) in the manuals. Why?

Now it’s just 47k

Flexibility is a range, so user can try what’s the best.

@mijostyn You don’t have any of the best MM or MI from the past and never owned any of them, I don’t know what can I say ... You must try! If you wish you can try not MM junk like your old Shure V15 MK-whatever, but a proper $1500-3000 MM. I never said MM is better than MC and I own some of the best LOMC ever made too (and I like them). Do you have some? Please post. If you think cartridges getting better and better every years you’re wrong. The problem with LOMC is the price, repair/retip is nonsense. MM are practically better and best vintage MM are cheaper and often better than most of the modern MC.

Modern MMs are junk because the cantilever and styli are always the same (from the same jewel manufacturers in Japan). Nearly all of them are nothing special. Maybe 5% is an exception, but not what you guys are posting here, not a Nagaoka, not Ortofon and not a ClearAudio with dirt cheap Audio-Technica motor inside.

SoudSmith cartridges are not MM, they are MI and it’s another story.

If you like expensive stuff buy this one.
Prepare to spend over $10 000 for this, it’s NOT an MC.
Then tell us how do you like MI or MM :)  

Chakster sold me a very nice AT ML150-OCC MM cartridge that I would be willing to let go if you are interested? Send me a PM. He highly recommended this cartridge and it is a good one especially at the less than $500 price point. It betters most MM sold today.

Sam's AT-ML150 OCC was nice, here is full description in my old sold listing. 

The ultimate in this series are the AT-ML170 and AT-ML180, but they are more expensive.