Lol at all the guys with small penises like 'It don't matter', when clearly, to many girls it does. It's something to look at after all and we humans like to be pleased aesthetically, evidenced by us males' desire to see some huge boobs. I fail to see a difference with regards to the size of a penis.
As to pleasure, it's clear that bigger penises = bigger orgasms for the ladies because, seriously, when have you ever heard a girl say, in films, books, real life or online 'Oh girls, his penis was barely seeable, yayer'.
You never will, unless the female in question has questionable mental capabilities.