From my short time growing, I've found that CFL's work great in a small grow space. But once you get over 8 or 9 sq ft, you have to throw so many bulbs at your plants that it gets a little out of control, ie moving all of those lights/cords.
I started my current grow using three 85W CFL's in a small cabinet and they did a great job vegging. Because my plants were getting too big for the cabinet and I had the room available, I bought a 4' X 4' X 6.5' grow tent and I found out fast that the CFL's weren't going to fully develop the buds. So I bought a 400W HPS with a vented hood and my buds have filled out nicely.
So my future game plan is to veg in the small cabinet with the CFL's and then flower in the tent using the 400W HPS.
A marriage of both types of lights.
If you plan to veg & flower in a small space, CFL's are an excellent source of light, but beware that the more CFL's you add, the more heat you're adding too.
