i would say depends on your set up.. both have pros and cons .. ive never used led's ,im pretty sure cfl is much cheaper . as leds use less power.
I sugest doing some more homework, and then decide which lighting fits your needs.. what might work for me might not work for you..
i honestly havent looked into LED very much. sorry i didnt really answer your question..
BUT as being on my first grow i elected to go cfl's as they are cost effective. so if the growing didnt work out or it wasnt for me. i wouldnt be out that much..
i plan on upgradeing to hid/hps for my next grow..