If you're only using the CFL's as a supplement to natural sun for the entire grow, then you will do ok. If cold weather is near and they will be under those lights the whole time, you will probably be dissapointed on the amount you get out of it. The more lights the better. You can make a home made fixture by wiring a bunch of those CFL's together, or you can buy a fixture and just screw the bulbs in. Like I said, the more lights the better.

In my first grow I was able to get close to 250W of CFL's into a plastic bucket I had at home. I painted the inside of the bucket with flat white paint and bought those black light sockets at home depot. I cut out holes on the sides and put the sockets through the holes. Then I wired the sockets together on the outside of the bucket. Finally, I cut a cord and wired it to the fixture. It worked like a charm and I had about 250 Watts for under $50.