I used shan masala too, as a matter of fact--the easy cook one, with all the grains already measured. I'm not that evolved yet
The keema biryani is pretty much the same as any other. It does cook faster, especially since I used chicken keema. The only difference for me is that in the recipe that I use, I add sliced lemons, chopped mint, browned-fried onions in the layers between the rice and keema. I like it since my kids will eat it without being too picky.