I bought Auber Instruments "Bisquette Saver for Bradley Smokers". They cost $21.50 for 3, plus shipping. They say they're lighter than other bisquette savers. Just for curiosity sake I used my kitchen scale to weight a Bradley apple bisquette and it was 0.75 ounce. I weighted the Auber bisquette saver and it was 1.5 ounces. I'm guessing the additional 0.75 ounce won't make any difference in wear and tear on the feeding mechanism. I'm going to try them out tomorrow.
If your interested here is a link:
http://www.auberins.com/index.php?main_page=product_info&cPath=14_28&products_id=111
I've been using the Auber puck saver rings for several years without any problem. At the time I bought them they were somewhat less expensive than the more popular solid and heavier ones everyone talks about on the forum.
(http://auberins.com/images/woodsaver2a.jpg)