I swear by S-189. Not a fan of 34/70. A Marzen is supposed to be malty and balanced. That's what I get from 189. I have made brilliantly clear and deliciously malty Maibocks, Viennas, Oktoberfests, dunkels, even light lagers with it. Ferment at 12 C, do the fast lager method, and no problems whatsoever. Have never done a hoppy Pilsner, so I can't say what it will do with that, but my experience with it has been very excellent!