I have a large iTunes/MP3 collection, and would like 'smarter' random playlists. I've come across BeaTunes in an Apple post - it's $35. I think it also tries to give you the key of the song, which is useful to me when I want to work on getting familiar with a particular key along with a recording in that key. I realize one can transpose any song electronically - I suppose that's a great way to get familiar with new keys also, by playing along up to tempo.

I don't suspect pinpoint accuracy - just ballpark...I realize the results will be far from perfect.

There are a few BPM analyzers out there. Has anyone tried BeaTunes and others (free or paid), and can comment on whether you thought it worth the money ? And which they liked best and why ?