There is no such thing as an effective "taste test", except for tren being the exception.
The lab that most people used has been shut down. Not all Test Prop causes pain. The Dubols (sp?) were a legitimate pharm grade test prop brand that was painless. On the other hand, Rugby, another pharm grade brand would make you think some medival age knight had rode by and smacked you in the ass with a spiked mace.