I test everything. I don't understand why everyone is not testing their gear. Serial numbers and lot numbers mean NOTHING. These are UGL products, it's not like the FDA is monitoring whether of not the lot numbers or individual vial numbers are legit.
Example form a source board I frequent. A new source pops up. Two members run the source's test-e on their lab rats and log it, each has several 20 ml vials from the same lot (per the numbers on the very pretty, very professional labels). First lab rat runs one vial, sides slowly kick in and gains start toward end of vial. Starts second vial, sides and gains drop to zero. Bloods verify second vial is bunk. Second lab rat shows zero sides and gains start to termination of cycle (at 5 weeks). Again, vials from the same lot.
Labmax tests are cheap. TEST YOUR GEAR. It's not MS, but it will tell you if you're administering gear or cooking oil to your lab rat. Your bro's experience with the same lot number means nothing.
Make your lab rat a happy rodent.