its not really a freak story of yeild but i switched from tubes to cfl''s and i am a new grower by the way. the growth boost from the light intensity change was extremly noticeable within 24 hours. Plus you get more lumens and more intensity which you need. i am goin to switch to a 400w hps system for flowering though so you might want to think of that combo to if you can afford it my hps system was only 140 bucks so its not a bad investment from everthing ive heard. hope i could help a bit