I never realized I was well-endowed until I met a woman who had a bit more experience than me. She kept saying, "I love your cock! But go slow at first..."
A few times she said, "I love your big cock inside me!"
I asked her, "Am I not normal sized?"
She laughed and said, "You're kidding, right?"
"No..."
"Most guys are this big (she placed her hand about halfway up my cock)."
"You're kidding..."
"Nope! You have the biggest cock of any guy I've been with."
"Does it make any difference?"
"Have you noticed how much I want you to fuck me?"
So that helped.
After a couple of MFM 3somes I realized she wasn't just making me feel good (she always did that!).
The reaction of the wives was all the convincing I needed.
Since then. I realized it's definitely an asset.