IMO the OM20 (nice nude eliptical stylus) is where the OM series starts to show its potential, it's worlds better than the cheaper ones. The OM30 is a step better, with a fineline stylus.
IIRC the compliance also goes up a bit as the stylus profiles improve, so the 30s and 40s work best with really light, stiff tonearms . . . i.e. SME III, Grace 707, etc., and setup starts to get a bit fussier. So I would recommend the 20 as probably the best price/performance upgrade for your tonearm.
IIRC the compliance also goes up a bit as the stylus profiles improve, so the 30s and 40s work best with really light, stiff tonearms . . . i.e. SME III, Grace 707, etc., and setup starts to get a bit fussier. So I would recommend the 20 as probably the best price/performance upgrade for your tonearm.