Hi Bill,
I think Pioneer DDJ SX is currently best choice for you if you are switching from CDJs to controller. It should be an easy switch for you. It is the best controller on the market.
I have been playing CDs as well, than I have switched to Pioneer XDJ Aero but I didn't like it. I am waiting now 3rd week for my Pioneer DDJ SX and I can't wait.
If you somehow find you are missing CDJs or turntables you can always connect them to you DDJ SX, but I guarantee that you will soon see how comfortable it is to have all you music on laptop. You can quickly search for tunes and you have waveform - things you can't have playing from CDs.
Did you ever consider Traktor scratch? You could be playing files from laptop, have all the advantages of it but control them with turntables.