Hey man... just a thought...
CFLs are fine if you just want to have fun growing...
But if you have any kind of respect for your budget, choose the biggest HPS you think you can get away with (heat wise), and go with the next size up inside of a cooltube with a kick ass fan...
Most people say they are on a budget and end up with a very high price per gram...
Use a strong HPS, it will give you the BEST GRAM/WATT ratio... therefore the cheapest buds...
If you are going to stick with it, you will end up with a bigger HPS, why upgrade 10 times along the way???
Your grow, your money... I've been there, and found myself burning over 400 watts in CFLs and small HPSs (I have 2 of the 70w and a 100w MH), so I ordered a 600W HPS and a 8" cooltube with a 265cfm fan...
With a cool tube and a big fan, you can treat a 400HPS
ALMOST like a fluorescent... 6 inches or so... you just can't beat that...
My 2 cents... your grow...
Go with what you know...
Best of luck...
Gypsy...