Andrek, I often use Grande and Dragone (made by Saputo) for my pizzas. They are quite different, but probably unlike many people, I consider them to both be of the same general quality. In a professional setting, the Dragone is much cheaper.
Grande has the best consistency, very creamy and smooth. It melts really well and covers the pizza with ease, even if you don't use a lot of it. Grande can hold up quite well under high heat without burning. I think this is because it has a decent amount of moisture in it that needs to evaporate before the cheese burns. Don't get me wrong though, somehow it is never soupy. When you reheat a slice made with grande, it tends to come back to life better than other cheeses. My complaint about the Grande is that the flavor is not the straight simple mozzarella flavor that I grew up with. In some ways I feel like it has other cheese flavors mixed in with it, and I would prefer to have control over that by mixing in my own special flavor cheeses. I have only noticed this with the grande processed mozzarella, not the fresh (in water) variety. A fellow forum member said that it tasted like Muenster cheese, and I agree.
Dragone is a dryer cheese. Because of this it tends to burn a little easier, and is not as free flowing over the pizza. When the cheese starts to cool down it tends to clump together a little more than the Grande. We have all had the pizza that is somewhat warm, and when you bite into it all the cheese for the whole slice comes off in your mouth. Dragone is not the absolute worst for this, but it does have that quality more than the Grande. With these melting issues aside, it is still a great cheese because of it's excellent flavor. To me it is a salty mozzarella, so I am careful about blending Romano in with it. If you do feel the need for extra flavor it takes better to Parmesan, Gruyere, and other less salty flavor cheeses. It is very milky and buttery tasting for a processed mozzarella, without even a hint of sharp or sour flavor.