I ripped my collection of 400CD's last Christmas and it took a couple of months in between having a life. I used DBpoweramp and a laptop which took on average 6-8mins to rip a disc to FLAC. A dedicated drive would have been faster but I was already fiscally challenged from the outlay of the Sonos, NAS combo and subsequent USB harddisk for a further backup.

Start with the most recent and most played stuff so you can start enjoying the benefits right away.