I think that wigs tend to look better on females than systems on males. I don't quite get it but wigs seem to perch in a way that is unrecognizable while systems seem to jut upwards from the scalp in a way that is a bit obtrusive like the hair is pointed forward.
I've never personally noticed this, and it certainly isn't the case for me. I think hair systems on guys can look fantastic and totally natural if they're done right. For me, as a guy with long hair, I could never imagine wearing a wig. I much prefer a hair system as it can be attached for longer periods of time (up to 2 - 3 weeks), can be totally customised and once attached looks and feels like I have a full head of natural hair.
But in the end, everyone has to look at all the options for hair loss - shaving their head, regrowing their bio hair, hair transplants, hair loss concealers, temporary wigs, semi-permanent hair systems, etc - and decide what is best for them.