you guys are referring to. Cooltubes offer only one advantage, and that is temperature reduction. Those "batwing" style reflectors are HORRIBLE in comparison to the traditional reflectors when it comes to putting the lumens down, and in a good amount/spread
cooltubes are the nuts! i run 2 1m cooltubes with 2 600w hps in each no fans or duct yet and home made reflector!!! and good temps