I just bought this lens for my walk around lens on my Canon 5D Mark II body. I do have the Canon 24-105 but it's to heavy to walk around with that lens, and I can not be discreet with that monster lens. Put this lens on my 5D and voila it's suddenly became my walk around and street photography lens, it's just like you only bring the body only, yes it's almost weightless, perfect.
Before I bought this lens I kept thinking of getting the Canon EF 50mm F/1.4 USM, but for me, 50mm on full frame body is still too long, and 35mm focal length sometimes it's too wide, that's why I took this lens instead. Well, long story short, you probably you have read a lot review about this lens, I don't want to repeat what other people did, so I just want to show the pictures taken by this lens. I just wish that this lens has F/2 and not f/2.8 aperture, but other than that it's a perfect walk around lens for me. Enjoy!!!