Unless you have a CD ripper program that is faster and you can live with MP3's vs. AAC files your largest impediment is likely your CD drive. I rip in about 1/2 that time with iTunes or less, so you may want to invest in a faster CD drive.
Keep in mind ripping without a program that will tag them via CDDB, you would then need to spend hours adding tags, so you need to factor that in as well.