Yes - it converts mono to stereo and looks really capable. It does not covert other formats to .wav or .aiff which is what I need - but I do that in iTunes. WHAT I HAVE NOT TESTED YET is whether I can convert .m4a into a .wav or .aiff.
I NEED THIS BECAUSE I have just found that rendering audio files out of Garageband means having an .m4a as a final product. I NEVER THOUGH I WOULD USE GARAGEBAND for anything but just discovered that you can apply Apple's iteration of AutoTune to any track. It works well (the technology was stolen from Antares when Antares forgot to protect it's patient in Germany).
From now on I will do all of my vocal tracks in GBand and then import them into BIAB or ProTools for further work.