I measure out ~10g of Burton Salts when I'm lazy and brewing something amber/dark in a German/British/American tradition. I'm not a fan of that mix though, because some things in it are just WAY out of wack. So yeah, only when I'm lazy.
If I brew Belgians (since I care about them so much), or am not feeling lazy, I'll add some gypsum, NaCl, and baking soda. Use a brewing program to see how much you need for the levels you want.
Hope that helps!