Snes9x has built in TAS recording, and is up to date (many Snes9x TAS versions are based off of 1.43 BUT, there is a version based off of 1.52, meaning you get the better sound core). Aside from the user-friendly GUI, I don't see why people claim Zsnes to be the best.
http://snes9x-rr.googlecode.com/files/snes9x-1.52-rr-r185.zip