The following link is to an interesting article on 5 lenses that are slightly longer than 50mm. It got me thinking...
I absolutely love my 50mm 1.8 and I use it all the time. It's sharpness and speed are awesome, especially for the cheap price tag. But I also find 50mm a little short on full frame for portraits. On a crop sensor, it's perfect for me.
Can an extra 8mm in reach make much of a difference? For me, no. The price difference between a 50mm 1.4 and 58mm 1.4 would never be justified. I personally would rather an 85mm 1.4.
Have a read of the article and see what you think.
Article date 25/4/2017