I have been reading these posts the past few days and it seems to be split on wheather to use lite or not,I think like other people have stated it is individual preference.My personal experience was that after using lite last year it definatley increased production and they layed well all winter...
Well honestly you wouldn't have to worry about your chickens freezing because with that amount of chickens in that size coop it is plenty warm,chickens give off alot of body heat.