Is money a limiting factor here? LED's can be expensive. What do you think most people on here getting good results are using? HID's ofcourse. Given your plants have good lumens(light) your lvl of THC will be mostly dependant on what strain you choose.
LEDs aren't quite ready for prime time. Probably will be the preferred lighting technology for growing in 2-3 years but not quite there yet.
Thats what I thaught too but ive seen some peoples grows with leds n a few of my friends and led's seem to work really nice
HIDs are definatly the best right now as far as good quality dense flowers. I was very qurious about LEDs when I first heard of them but I have yet to see a really nice dense harvest from them. THC quality is mostly seed genetics as far as I know and different lights will not change that. Thats my opinion anyway.
Have you checked out this G.C. jounal yet http://forum.grasscity.com/indoor-grow-journals/464971-growing-180w-jumbo-ufo-14.html#post6347733 or this one http://forum.grasscity.com/advanced-grow-journals/485301-rumples-led-challenge.html or read this High Times article High Times > Light and the LED Zeppelin: Will LED’s Sink or Soar in the Growroom? typicaly HID lighting will use a couple of watts in cooling for every watt for lighting just keep that in mind.