LED Vs HPS 400w YIELD

I have been trying to research comparisons of these two, but it seems there are only like 3 experiments of the comparison and only one of those describing the yield comparison. This is the link YouTube - LED Marijuana Grow. (In the video The 400 watt HPS more than doubled the UFO LED yield and finished budding much quicker, but the UFO vegged way faster). I was wondering whether any of you have first hand experience with the LED lights HID Huts UFO or the PROCYON 100 vs 400 watt HPS's. And how the yields compare. I'm interested in getting one...

well then in that case if the LED vegged faster then why dont u get that for vegging and then get a hps for flowering if the hps flowers double!!! gooood luck dude hope all works out