I've owned the Shure and liked it, but remember that it's no longer manufactured, and at this point I'm not sure you can even get a new stylus for it. NOS ones seem to bring $500 or more, so the price difference with the currently made A-T gets even bigger. The A-T always get pretty positive reviews.
Unless you have a line on a reasonably priced NOS Shure or a known good used one, I'd stick with the A-T so that you can get warranty and service.
Another approach would be to go cheap with somehting like an Empire EDR9 or 750. Do a search here for the threads - many people love them. I just mounted my EDR9 and my initial reaction is that it's better than my Shure ever was, and I don't even have it in the right tonearm yet. YMMV.
David