Its only a few watts for CFL vs LED, returns are diminishing, though percentages can be high. LED also has some power differences based upon color temperature.
I have a Cree 40 and 60W bulb here. The 40W (450 lumens) claims 6W, the 60W (800 lumens) claims 9W.
I did a test where I put a few different bulbs into an old chandelier in our home. I had a couple 13W GE CFLs, that are around 825 lumens, the "40W" Cree in the same color temperature, and then the Cree "60W" in "daylight" color.
The Crees were in the far left (blueish, 60W) and far right (cool white, 40W) positions. The other spots were 13W CFLs.
While the closest position (a CFL) looks brighter, looking at it in person, you cannot see that. The 40W LEDs look the same brightness and the same light throw as the 60W CFL.
So practically speaking, IMO you can get the same light for 6W from LED or 13W from CFL. I dont have the lumens rating for the CFL.
I like LED bulbs, only have a few, but when these US assembled Crees came out in HD for a relatively decent price, I had to bite.