The spectrum is VERY important!
I have 6500K 23/26W (actually watts, not equivalent) cfl's and just purchased some 2700K 42W cfl's. Both I found at wal-mart. I haven't found 6500K in anything above 26W (unless you go to a hydro store).
You want MORE BLUE for vegetative growth and MORE RED for flowering.
I had no "red" bulbs (they're actually closer to orange) for my veg, although it won't hurt, just make sure you have majority blue.
The sun is only more red in the fall, close to harvest time (hence the "flowering" stage)
Mainly, the color (K) is more important. Find the right spectrum and then look for the highest lumens you can get in that spectrum.