If you don't know what box squatting is, check out this article by Louie Simmons. He can explain the how's and why's better than I ever will be able to. Now the snatch grip deadlift is new to me, in practice at least, and I am loving it! Just deadlift with a super wide grip. This drill will smoke your upper back and your posterior chain as you have to squat much further down to begin. Give it a try for something different but prepare to be humbled. As for the prowler, for me it is a great finisher. It works your legs, hips and arms and gets you sweating like a fat kid at a swimming pool! Everyone needs to increase their GPP and this is a great tool to do so that will make you stronger at the same time.
I think kettlebell lovers will really enjoy pushing a prowler around. Training with one gives you that same over the top conditioning exercise that we learn to crave!