iTunes vs Google Music vs Xbox Music vs Amazon Cloud player

I've been looking for a way to clean up my MP3 collection, and I know every one of these services allow you to use scan and match to upload your tracks to the cloud. But iTunes match looks like it's the only one that allows you to upload songs, and then re-download better quality songs if you want to re-download on your computer.

So if a user like me is basically looking to get a service, not even to listen to the music but just to clean up my mp3 collection (better quality, album art, id3tags etc), what would be the best route to go with? From what I've been looking at it seems like iTunes is the only one that allows you to re-download songs, unless I'm mistaken.

Thanks in advance