iTunes Match downloads

I've had iTunes Match for several years, and its been a great service. Unfortunately I lost my original files that the cloud "match" songs were gathered from. Many of these were not iTunes purchases, but instead CD's I'd converted to MP3's in the past or even mix tapes/personal recordings of songs never made available for purchase.

My question is, if I download the iTunes Matched songs from the cloud are these my files to keep forever again or would the downloads cease to work if ever were to cancel the iTunes Match service. This is particularly important to me as many of the songs I have stored by iTunes Match are not available for purchase or streaming elsewhere.