THANKS. A. LOT. ALAN.
sigh... its time to move from these zooms to primes. the only zoom ill be keeping will be the 70-200 as its the perfect lens for portraiture for me aside from the 85L that i plan on getting in the next few years.
so you've tried the sigma? and you returned it because it had issues? hmm.. DANG IT! i want a perfect 50! it's the perfect focal length for me.. not too wide... not to tight either.
DANG IT! DANG IT! DANG IT!
Dont move from the zooms. Zooms are wonderful as long as you know the limitations when lack of light becomes your enemy. When you get your 24-70L you'll see how incredible the 5dmkII becomes alive with dreamy bokeh.
Go and buy your Sigma 50mm but be warned it'll be about a good month before you see it back "if" you send it out for calibration. Not sure how the lottery goes but you can try several copies to get a perfect one.
The Canon 50 f/1.4 is "good" for bokeh. I still think it has pleasing bokeh for the price. Just remember that people on the POTN are more critical in bokeh quality compared to people "unfamiliar" with photography skills and terminology. Buy a Canon 50 f/1.4 so you'll have a solid AF performer. Later if your not satisfied buy a 50L (roll the dice for no focus shift) or a sigma 50mm without back/front focus issues.