Does anyone have any experience with any programs (preferably Mac) that will review your mp3s, determine the BPM, and then record it in the tag? Would be helpful for creating playlists -- my downtempo/chillout genre has gotten so large as to be unmanageable, and I'm thinking this might be a quick way to help sort it into smaller, more specific subgenres.

Programs I've seen include:

Tangerine BPM Analyzer beaTunes BPMer

Anyone use any of these, or have other suggestions? Thanks for any input.