The physical connection of the XLR is better. They lock together and the contact from pin to socket is better. There is a clear standard so you can use connectors from different manufacturer's and not worry if they mate well.
There is no real standard for RCA connectors so one manufacturer's male might not mate well with another's female and vice versa. That is why some SE manufacturer's tried to move away from the RCA's, like Naim did with their DIN connectors, but it never caught on as a standard.
There is no real standard for RCA connectors so one manufacturer's male might not mate well with another's female and vice versa. That is why some SE manufacturer's tried to move away from the RCA's, like Naim did with their DIN connectors, but it never caught on as a standard.