Both Apple music & iTunes match 'matches' and uploads songs from your local library, Uploaded tracks remain at same quality and same format DRM-free.
Any matched songs for Apple music get matched to 256kbits AAC in the store (DRM).
Difference is any song in Apple music catalog is DRM... iTunes Match is DRM-free. With both services, any song u own, is yours, so download your music before u cancel, or keep a backup.