I would say 2-3 weeks per shot. But I also do them 3 or 4 times - there are many ways to approach a given shot and sometimes you can't tell until the very end which was the best way. Sometimes it all looks fantastic and then falls apart somehow in the grading, when dynamic range is maximized and colors pop. And I really want to choose the best of the approaches to get the best results, so it takes time. Plus, in cases where you just have a lot of rotomattes to build, etc., that's labor/time intensive.

I have one set of custom tools wrapped in a container called Beelzebub - those were developed by guys who were strictly against commercial enterprise; pure-research guys. I have to honor that, plus keep asking every year if they've changed their minds yet. :) But I have absolutely ZERO software snobbery - I will throw anything at the shot that works best, and sometimes it's surprising. Sometimes some little plug-in in After Effects might handle a particular issue better than a $10k piece of software. On the commercial software front, I use Cinnafilm's Dark Energy Pro, DaVinci Resolve, The Pixel Farm's PFClean, Nuke, After Effects, Photoshop, and Imagineer's Mocha Pro among others.