2" or 3" deep baking pans? Why?
Two inch because layer cakes are typically four inches tall.
I have some of both and I like my 2". If you are going to torte at all, the 3" cakes are way too tall.
I have both, but use my 2" pans for majority of my cakes. Like stated earlier, I believe most cakes are 4" tall. I do use the 3" pans when I am doing sculpted cakes, like purse cakes.
I like my 3" pans but I only bake 2" layers in them. I find that I never get a true 2" layer in my 2" pans. Case in point, the cake I just took out of the oven - it's only about 1 1/2" tall If I had a 3" pan in that size one of my next purchases!) it would have been 2" tall even if I'd only put in the same amount of batter.