im sure there are some other good brand options. personally ive used all 3 cannon 50mm's and i bought the 1.4.
the 1.8 is good if you are on a really tight budget because its only about a hundred dollars. its pretty sharp and fast enough for basically anything. it also has a macro focus which is pretty sweet for some close ups but nothing major. it feels like a toy because its plastic and the focus ring is weird and a little awkward. but the image quality is good. i used this for a whole project that i was happy with. and also helped a friend on his project where he used it as well. i think it does video a little better than picture.
the 1.4 is awesome. much sturdier and solid feeling plus the focus ring is solid. the image is super sharp and really awesome for pictures and videos. i ended up buying this one and used it last weekend at a wedding and it was perfect. awesome lens and super happy with buying it. its really not too terribly expensive, but it is 3 time more than the 1.8
the 1.2L from canon is probably one of the cooler prime lenses ive ever used but we shot a project with that lens on a red. plus its ridiculously priced for the other two options that are still both really good.
if your on a budget, 1.8 is fine, if your not so much on a tight budget, i recommend the 1.4. those are just the canon lenses tho, there may be better/cheaper other brands that i haven't used