Not sure why it's only showing 1 iteration on the HTML page. It was set up to do 10000 iterations and took that long to actually process. Let me go back and make sure that there's not something funky going on. Thanks for pointing that out.
**EDIT**
I went back and updated my original post. Nothing changed significantly except for the dps increase it showed was about 800 instead of 1.2k. The relative ratings of haste/mastery/crit didn't change significantly from what I mentioned before. Namely that it seems that with 4pc Mastery becomes more attractive than haste with the BiS gear. (This could change if haste drops below the nearest extra VT tick)