Ever since No2 came out it had controversy. Now it seems to be a hot product that makes perfect sense. More blood flow, oxygen, ATP, creatine are all driven into the muscles using nitrogen or nitrix oxide.

My question is since there are so many complanies making them now, which ones are the real deal and which are knock-offs?????
--BSN Nitrix
--Muscletech Pump Tech
--VPX Muscle Nitrous
ETC.