So, I’m looking at getting a Canon EF-50mm F/1.8 lens for my Canon Rebel. The price is right, and it’s the kind of low-light performance I’d like to have again on a camera, and frankly I just like prime lenses more than zooms.
So, does anyone here have any experience with these lenses? Am I better off with the original metal body one, or the newer plastic body one? If you’ve used both, are there any reliability issues with one versus the other? What are the best places to buy them?
So Photo-Dopers, enlighten me with your wisdom! 
Can’t tell you about your exact lens, since I use a Nikon, but I can tell you about my Nikon 50mm f/1.4 lens I bought in August.
I am very happy with it, it has excellent low-light performance, and I can get an extreme amount of blurring in the background of portrait shots.
My only disappointment was from the crop factor. Unfortunately, digital cameras often have a cropped, smaller field of view compared to the same prime lens on a film camera.
In order to get a field of view comparable to 50mm on my camera, I would need to use a 38mm lens. Unfortunately, though such a lens might have the same field of view as a film 50mm, it would not give the same “as the human eye sees it” appearance that the 50mm is famous for.
In other words, to get the straight lines and natural portraits (without making women’s faces look fat), you still need the 50mm, but you will find that the field of view is somewhat unconveniently small – you will be backing up to get people in the photo.
Good luck with your lens!
Well, I know that they make special smaller lenses for Canon and Pentax DSLRs (so a 50mm DSLR lens works just as a 50mm lens should, only on the digital camera and not hte film one). I’d assume there’s something similar for the Nikons kicking around.
And I suppose, if it all came down to it, I could just spend $30 on a Pentax Screwmount-EOS mount adaptor and use my trusty old Asashi Super-Multi-Coated Takumar 50mm F/1.4 prime lens that weighs as much as my whole Canon Rebel, but then I wouldn’t have the autofocus and camera-controlled aperture.