which is better ? MC phono stage or MM+step-up ?

I had my phono stage heavily modded by Bill Thalmann. We decided to go with an EAR MC-4 SUT for the MC gain, so the phono stage is run in MM mode (all tube), bypassing the JFET in the MC portion of the signal path.

The result of SUT + tubes is a much more musical presentation with a lower noise floor. Bill reminded me that CJ's top phono stage has a SUT built-in, so it runs SUT + tubes in the signal path.

For the dollar invested, a "quiet" tube sound with lots of quality and flexibility.

We've specifically avoided using SS input in our tube phono section. Instead, we created the first fully-differential phono stage (1989) as a means to keep noise down. I've tried a variety of SUTs (and never had a hum problem, FWIW).

SUTs do offer a great noise floor, but at a slight loss of detail and musicality. We did everything we could to make sure they were loaded correctly- BTW if not properly loaded the SUT will express the inter-winding capacitance rather than the turns ratio- IOW loading is **essential**. I am sure that with some preamps, the SUT is an important part of getting a LOMC to work, but with our preamps as longs as the cartridge is over 0.2mV going direct sounds better.

Well, I do have a tube phono preamp with total 72 dB phono gain - sans line-stage.....
Nevertheless - I do run my LOMCs with a SUT. I have sufficient gain, but that is not the whole issue. Its not just gain - its the matching impedance AND inductance. Something only the matching SUT can supply for a given low source impedance moving coil.
But after all - that is just my opinion and I do use very low source impedance and output moving coils.
Back in the early 1990ies I too thought that running LOMCs direct into the phono stage is better.
Today I use very special SUTs hand tailored to the cartridges I use.
The LOMC and its matching and corresponding SUT are a team.

And yes - I agree with Atmasphere regarding avoiding ss input stages in tube phono preamps. Tempting as it is (oh, that extra gain...) - the trade off (sonically...) is too high a price. There is no free lunch ......
But in tube phono stages the prime slogan still is: "straight - no cheaser !"
While I have to admit that the JFet tailed hybrid input stages are always tempting from the point of view of a designer.

Yes, I have been told that getting the jfet gain stage to really sound right is not easy, which is why there are many bad examples out there.

I'll leave it to others to sway toward one approach or the other. I am only offering that there is more than one way to get to the music which is why there is a number of great phono stages available and they don't all use the same gain stages. There has to be an equal number of really bad ones of all designs. So, IMO there is no simple answer to the original question. As always, you have to live with/listen to any device for yourself and decide.