So I decided that in order to be totally fair, I'd give iTMS a chance. I didn't hold much hope for them, but since I had not yet actually tried their offerings I felt it was a little unfair of me to dismiss them out of hand.
With that in mind, I set out to compare the two. I found three songs (well, two entire albums, but I'm not about to spend more than a few dollars on this project) that were offered by both services, two of which I also had a copy of the album that I found in a used CD store. So I decided that I would get the three songs from each, compare them to one another, and then I would take the two I have the CD for and dump them to wav and compare the raw sound to a raw rip off the CD. That way I would not only be comparing the two services to each other, but I would also be comparing them to the actual CD (to test the claims of "(near) CD-quality music" both make).
I did the first phase (comparing the services to each other) on Saturday, and this entailed listening to the songs multiple times at key moments of the songs across different headphones and devices, so no one encoding method would be favored by the different equipment used for playback. If anything, it could be argued that since I only used Apple products for playback that my method favored iTMS -- I'm being generous and assuming that Apple would not stoop to encoding their songs for optimal playback on their devices (besides, my hypothesis is that they are 'crap' compared to Emusic's offerings, so I'm allowing them the "homefield advantage" if there is to be any).
My findings have proven to suprise me. I was unable to discern any difference between the files downloaded from Emusic and the files downloaded from iTMS. In every listening scenario the two songs were auarly equivalent. If one of them had a slight background hiss-pop from the record the DJ was using, the other one also had it at the same place. One song had an annoying high-pitched *snap* at one spot that I hadn't noticed before and yet it turns out that the other service's song had the same snap at the same place (unfortunately now I can't listen to that song without noticing it -- good thing it's not a song I spend much time with). The only differences to be had between the offerings from both services are in the technical details. A song from Emusic takes more space than the same song from iTMS. Where iTMS does get close to the 1MB/min level, Emusic is something more around 1.3~1.5MB/min. This is easilly understood as comming from iTMS using newer audio encoding technology where Emusic uses older tech. They both achieve the same level of audio quality, but iTMS can do it in less space. Personally, I feel this is a more than fair trade-off when you consider the (in my opinon insane) restrictions that Apple places on the consumer where Emusic has no such restrictions, but that's just my opinion.
Perhaps tomorrow or next weekend I'll get around to comparing the songs from the two services to waveforms pulled straight from the CD, but for right now they are looking pretty damn good. I'm keeping notes in a textfile and will give a complete review when I'm finished.