Comment Quick & "dirty" spectral analysis (Score 4, Informative) 48
Just take a common CD and hold it up so you can see the "rainbow" reflection for your light source. If it is a continuous "rainbow" then it's likely going to have good color rendering. If you see spots of color, then it's emitting peaks of various colors. My old "warm white" CFL's were peaks of about 6 colors. I hated them, but they were all that was available until recently.
Now I use "Bright White" CFL's which have what looks to be a nearly perfect, continuous spectrum. The best part is that they aren't yellow or blue tinged, they truly are a nice, crisp WHITE. I'm hooked.