double syncro?

[CarPsyco84]

First off, I drive a 90' Talon AWD, turbo, 5 speed.
2nd Gear has yet again to go to the crapper, 1 bad shift and the syncro's shot and it grinds. I've herd alot about using a double syncro 2nd and how its soo magical, but I've never been able to figure out what exactly you do differently. Is it just a syncro, if so, where do I get it. Or does anybody know if the solid brass syncros work good, without failing from 1 bad shift, like the ones with the fiber inserts? Any know how on this would be great...