i have dr120 tent in spare room with window slightly open for ventilation but light proofed as in uk. anyway at mo i have 5 plants various strains and 2 250w red cfl in barn reflectors and 2 105w blue cfl hanging down middle to stop stretch and add side lighting. temps around 75 with tent half open and fan blowing 10 mins in every hour currently in flower 2 weeks. my dilemma is i think i need more side lighting as plants are around 2 foot high .anyway thinking of buying 4 more 65w cfl made by greenlamp but temps would go up and have no extraction of hot air hence why leave tent half open. but also thinking on cutting losses on cost paid already for cfls and bits £160 and getting a 600w dual spec hps in parabolic reflector £130. my question is which would be better? which would give less heat? and which more yield. and electricity is also a factor. or i could get 2 250w self ballasting mh bulbs £15 each but was put off those for various reasons. 1 being no one has any experience in them. any help deciding would be much appreciated thanks in advance. peace to all