IRBD, I envy you, man. Very nice setup you've got. Strong too!
One suggestion on the atlas stone: Turn your belt around so that the buckle is in the front and then make a little loop with the unused part of the belt (e.g. don't tuck the free part all the way into the loop) so that your belt has got a little "belly" in front of your stomach. When you initially deadlift the stone into your lap, this protrusion on your belt will then act as a support under the stone when you shoot it upwards with your hips. Trust me, this makes a huge difference, especially when the weight becomes very heavy.
Hope this makes sense...