After much deliberation I have finally decided to purchase a 50L. I was contemplating whether to get a 50L or try my luck in the "Sigma Lottery" and purchase the Sigma 1.4.
After a few weeks of research and deliberation, I finally made my decision based on three main reasons. First of all was the fact that there's a Canon Service Center here on Oahu (if I do need to get it calibrated). Secondly, I didn't want to take my chances on a third party lens (although B&H has a 15 day return policy and Sigma provides a 4 year warranty). Lastly, was the fact that the 50L has weather sealing and I love the build and quality of my other L's.
I hope I made the right decision and that the extra $1000 was worth it.
The pictures in the 50L thread are truly inspirational. Hopefully I get a "good copy" of this lens and the learning curve for fast primes isn't too bad. If I can learn to work with primes, I may end up selling my 24-70L and picking up a 35L. 
Sorry for the long read, I just wanted to share my excitement. 
-tyler






