I would say i agree, with 500 mg gear its very hard to save some place for oil. It should be pretty much solvent and raw material of steroid which will create huge pain. In my opinion max should be around 400 mg/ml but only with highly soluable steroids with long esters like Decanoate or Undecanoate. Otherwise it will crash after manufacturing or crash inside your muscle which will cripple you for 1 week