KFC - It can use either interface. It's like using Winamp 2.9's database in terms of speed, but much more flexible. I've only got a PIII 800 and it didn't do a Musicmatch 8.0 or anything (ie- get up an leave for 45 minutes 'cuz you're not going to do anything else during its scan). The machine was perfectly responsive during the scan, as was the RMM software. A full scan took about 4-5 minutes. It's like the scan is a lower level background task. I've got (I just checked) 6251 tunes taking up a bit over 32 GB. You'll like it, I promise.

-Zeke