Cory rods. Length.
I have both the 5.75" (Cory rod) and the 6.5" (New Cory rod). You will see posters on CG insist that the 6.5" works better. I haven't had problem 1 with either rod. Neither has stalled and find that they work identically well with my process.
B|Java
Dave,
I don't believe that either rod 'works' better than the other, all things considered. However, the larger glass rods have a little more mass to them, and that makes a bit of difference. If you allow the heat to get too high, the normal size glass rod will bounce, and a heavier glass rod will stay in place due to the extra weight & will be a lil' bit more forgiving, IMHO.
Same deal with the filter issues. If you have an outstanding grinder, glass rods are the way to go.
If your grinder produces a lot of fines, they will clog either type filter, and I believe the cloth filters are a lil' bit more forgiving, again, IMHO.
Which reminds me, It's almost time to replace my Rocky's burrs...and replace the gaskets in Miss Livia