i've tried a lot of alto mouthpieces(including links,) and I own a meyer 5. The 6 is better suited to most people.

May I suggest a different approach? First ask yourself what do you want to change in your current sound. Do you want the sound to be brighter, or darker, more focused or broader, warmer or more screechy (in a good way)? Then look at your current mouthpiece. Does it have a high baffle or a low baffle. Large chamber or short chamber? Straight walls or rounded walls? Short facing or long facing? If you are playing a high baffle, short chambered metal mouthpiece, and you want a wamer sound, then going to a rubber mouthpiece or a larger chamber might do the trick. But at the same time your air will travel slower and you will loose some projection. The Otto link is a larger bore, lower baffle mouthpiece. If you want a more rock & roll or fusion kind of sound, then try a higher baffle and a shorter chamber. But at the same time you will have a little less control over the horn (due to the faster sir) and you will tend to loose the lower notes. But you might find the altissimo will come out better. A bobby dukoff is a typical high baffle short chamber mouthpiece. Also remember that the mouthpiece has to have enough volume to complete the conical bore of the sax. If it has too much volume or tool little, your sax will tend to be out of tune with itself when you use it. In general older saxophones need larger chamber mouthpieces. Your 1977 horn probably doesn't need that large of a chamber. And also keep in mind that metal moutpieces don't vibrate as much as rubber ones, so the metal ones will have a more focused, fusion sound, while the rubber ones will have a broader, mellower sound. There is a little science behind the mothpieces, and if you do a little studying, you can probably narrow the choices of mouthpieces you want to try and may be able to get away from sifting through everyone's anectdotal experiences.