I have been using it over a year now and and generally quite satisfied and agree with the other contributors comments.
The only thing I find really frustrating is once your library has been scanned, if you make any metadata changes (changes to cover art come to mind), Match will see the change and change it back to what was originally scanned. So far, the only way I have found to get around this is to edit the metadata with an external editor and save it. Delete the file from both iTunes and iCloud. Wait 24 hours (it can take some period of time for the iCloud serves to make it's changes). Add the edited file back into iTunes, then let Match do it's thing.
Quite a process just to update some metadata.
If anyone has a more streamline process for this, please let me know.