Looking real good! Great oven spring. How much IDY did you use for this batch?
I have been very happy with my Pizza Bella--making all sorts of pies--NY White, New Haven clam, and lots of good ol' Margheritas too. It's nice to be able to get a stone that hot, that fast, isn't it? I really recommend getting your hands on some Caputo Pizzeria flour--it really is as good and tasty as everyone mentions at these high temps. Caputo bakes up softer with a more delicate crunch than the KA flours, and has more flavor...
With my Bella at 800F, I too have found 3 minutes to be the ideal bake time. If you want your cheese less cooked, ala Neapolitan, I use big chunks and keep them icy cold right until baking. It does help. I have used East Coast fresh mozzarella, Polly-O, as well as fresh California Mozzarella (which is firmer and more mellow than East Coast style fresh mozzarella), and the California cheese has held up the best for me in the little Bella unit (Mozzarella Fresca brand).
Keep us posted as your experiments continue...!