While it's not cheap, the Sigma 50mm f1.4 lens provides great value for the money.

It would be nice if it had image stabilization

My reaction to every fast lens Sigma release seems to be "I can't believe something this good costs less than $1,000." A new favorite -- the 50mm f1.4 DG HSM -- joins Sigma's Art series of lenses, which already includes two of my all-time sub-$1K favorites, the 35mm f1.4 and 18-35mm f1.8 .

The Sigma 50mm f1.4 lens is a well-designed lens that performs very well for its price

It would be nice if it had image stabilization

Required factory focus recalibration. Still slightly front focusing, most noticeable wide open when there's little DOF. Re calibration process was painless. I paid to ship lens and camera body to sigma in Long Island NY, and they took it from there. Got it back in a few working days.

Image Quality Bokeh Fast; Nice Bokeh; Strong Construction

Blurry Focus

Every camera film or digital has set a benchmark. The images are truly world class and delivers excellent contrast and sharpness even in low light conditions.

I was scared after reading reviews that it has some back focus problem... but it was fine! Plus, if there's any problem, you can always return and get a new one.

Consistent Output; Durable; Easily Interchangeable; Nice Bokeh; Rugged; Strong Construction

Heavy

The 'EX' in the name denotes this lens's superior optical and build quality, the 'DG' means that it's optimised for the smaller sensor areas of most DSLRs but will still work on a full-frame camera, and the 'HSM' stands for 'Hyper-Sonic Motor', Sigma's proprietary high-speed autofocus technology.

I was weary to buy this lens due to many review of the autofocusing not behaving. I bought 2 copies to hope that one would work with my camera. I noticed within the two copies that one was softer than the other. The autofocus is also not super at low light situations.

Great lens! I don't know how else to describe this lens in 50 characters

An beauty glamour headshot image taken with this lens @ f9.0 in studio with a Nikon D90 along with some brief details are avail for view here: http://glamourphotography.co/?p=6588 Some may say f9.0 is not a fair test of a fast portrait lens....

Great Bokeh; Very Sharp; 77mm Pro Filters

Large Green Ghost images from highlights wide open; sometimes

Amazing lens! I absolutely love it - everything from build quality, Bokeh, image quality, this lens absolutely shines!