70’s rock pressings. Witch equipment deserve?

 I go for the original if I can find it- original press from the country where the recording was made. But if the title isn't that important to me I often pick up a reissue.

I have never seen a Grace, Stanton, Pickering, Audio-Technica, Pioneer, Garrott ... with softened or stiff rubber damper in my life.

I have seen this multiple times with Shure, Pickering, Stanton, AudioTechnica, Empire, Grado but some of the others you've mentioned I've no experience. However the operating principle is the same so unless the manufacturer developed a very special suspension material my guess is that you have been very lucky or (more likely IMO) the cartridges might seem to be performing well but would sound smoother and more detailed with a stylus replacement.

Grado GOLD is relatively cheap cartridge, i like Grado too, but by reference Grado is Signature model from Joseph Grado (model XTZ).

Yes, we’re running one of those in our shop turntable.

No one would buy all those expensive vintage cartridges if there could be any single problem with suspension or anything else,

What?? Of course they would- because they don’t have a good reference for knowing how the cartridge performed when new! The only way I would buy an older MM cartridge would be if it had a replaceable stylus and I knew i could get it. The cartridge body will last indefinitely and the stylus is very hard to wear out, but the cantilever suspension is the tricky bit and pretty vulnerable to the ravages of time. I’ve brought some back to life by applying a small bit of brake fluid to the suspension and letting it sit for a while positioned in such a way that the fluid didn’t contaminate the stylus. But that’s really a move of desperation (although it did buy me nearly a year before it was obvious the suspension was just gone). It doesn’t always work, depending on what happened to the suspension when it perished- did it get hard or go to goo? If hard, there’s a chance it will come around. If goo, you’ll need a new stylus.

Finally, you should tell us what is your favorite new MM cartridges and how many of those greatest vintage MM did you try and actually compared to the modern MM ? Also it would be nice to know which modern MM you could compare to some of your new LOMC

I like the Grado cartridges. We use a Grado Gold mounted in our SL-1200 to play back tracks we've cut on our Scully  mastering lathe. Its a sort of standard- if it can play it back, we've not overcut it. And we've shown that it has bandwidth past 35KHz mounted in that arm.

Anecdotally I've run a Transfiguration Orpheus for some years. One time a channel failed so I had to send it back. While waiting for it (or a replacement), I was jones'n for tunes and realized that I had a Grado Green (at the time, retail of $35.00) sitting new in the box. Since my Triplanar is very adjustable, I set it up and took the time to do it right. It was at this point that I realized that the ability to track the cartridge correctly was far more important than the kind of cartridge you have; the Green tracked perfectly  although it sounded a bit 'up front'. Then I remembered that loading is critical on high output MM cartridges; once I get that right (using a 10K resistor) it was quite relaxed and other than having more output, was not significantly different from the Orpheus in any way I could discern. I threw some real torture tracks at it and it was effortless.

The main concern anyone should have using an older MM cartridge is that the suspension for the cantilever perishes over time; whether you are using the cartridge or not after 3-5 years it simply won't meet spec.  

@ramon74

Technics are great turntables. Their tonearms are not nearly as good as the turntable is! The same goes for their platter pads.

1.- buy yourself a nice vintage MM cartridge from the same era with Line Contact type stylus (avoid spherical/conical or elliptical). 

I would regard this statement as entirely false! The cutting stylus used on any stereo LP is the same today as it was in 1958. Newer stylus used in brand-new cartridges work just fine if they are set up right. Vintage cartridges OTOH are risky and lower performance (cartridges have made improvements in the last 50 years...); but in particular they will need a new stylus to work properly!

As with any other genre it pays it have the original pressing; rock is no different!
The originals of King Crimson, Yes, Jimi Hendricks, Crosby Stills Nash; too many to mention, but yes, it pays to have good playback. There are some awesome recordings out there!!