First, make sure you have 8GB RAM in your Mac. Once I upgraded, things began to run a lot smoother. Kjams & OSX will use all of 4GB easily. Once you have an extra 4, iTunes or Safari in the background are no longer an issue.
Second, search speed. I was having problems adding new singers during a show on a 1TB WD Passport USB2 external. Searches that returned large amounts of data (Search for Elvis, or Beatles) hung the lyrics for a few seconds before they posted. The person singing was left with music playing and lyrics stuck on screen for a few seconds. I purchased another WD passport, but this time I went with the Firewire800 drive. I used Carbon Copy Cloner which took about 8 Hrs to copy my 1TB drive. Today, I can search for ANYTHING and once the search is complete, it posts immediately with no noticeable delay to the singer that happens to be performing at that time.
All in all, for less than $200, my show system is now as speedy as it can get. I hope this helps someone in the future, and more importantly, helps Dave from me bugging him daily.
