Bought this from Amazon recently, was really impressed with the quality of the build on the lens, real solid hefty piece of kit yet small enough for me to carry around!
Was testing this out on my new Canon 550D, the video recording on it was absolutely amazing! Crisp quality! Would definitely recommend this to anyone!
The f/1.4 was a real joy to play with and i was thoroughly satisfied with it, the sharpness of my pictures and the background blur was a nice touch which added more emphasis to the subject in focus.
Until i took a couple more shots, and realised the focus appeared to be slightly to be off.
Prior to purchasing this lens, i'd read about the lens having alot of front/back focusing issues, so i wasn't too surprised, but was abit disappointed.
Didn't realise until i tried focusing on certain points, taking picture and upon closer inspection of the image, i'd find that the point of where i intended to focused on, was off by quite a margin. Although slightly disheartened, i am not going to give up trying to find the 'perfect' working model of this lens.
A word of advice, though not guaranteed - check the serial number on your lens/box. Supposedly later batches of the item was less likely to have problems.
A word of recommendation, get the B + W 62mm UV Filter with Multi-Resistant Coating, cheap solution to protect your lens and give you a nicer picture!
Goodluck & Enjoy!