Creatine mono = no delivery system into the muscle. Some of said creatine stays OUTSIDE of the muscle and causes "bloated" feeling and soft look
di Creatine malate, magnesium creatine chelate, CEE, etc = delivery system to force creatine into muscle causing 'muscle fullness' feeling and pumped look.
But when it comes down to it, creatine is creatine. People just argue which delivery system is better for getting the highest amount of creatine to it's desired location - the muscle itself