Yessir, that there's some light bleaching, AKA heat stress. It's from the heat actually, but basically the heat of the bulb causes the cola to fluff out and grow foxtails/donkey ears and the excess lumens seem to bleach out the vegatation in that area.
You're right - it doesn't affect potency or taste perse, but it does definitely affect bud density which will be much less than a bud that's not been afflicted with some form of heat stress, or 'light bleaching'.
I would suggest getting a 400 - 600w switchable HID light and back it off to about 18" from the tops of the plants. Or if you want to stick with the UFO then just flower your girls in a SOG method much earlier. Have more total plants to make up for the smaller size, and still keep the UFO about 12" away from the tops. The lumens from a UFO will never reach lower than about a foot down from the tops and those CFLs aren't going to help much either other than to cause more heat.
those are monsters
