IMO, "legit" peptides isn't the real issue here.
Even if the peptides are exactly what they say they are, that doesn't guarantee they'll be safe or effective for you. Too much vitamin A can kill you, and that's 100% real vitamin A.
There hasn't been extensive research into dosages or long-term effects on large groups. Some people will definitely have bad reactions.
Basically, we're acting as our own guinea pigs.