I'm getting ready to do my first topsy turvy cake using styrofoam wedges instead of carving and stacking the tiers. My question, is there a specific type that is better than another? I have seen styrofoam in the arts and craft section, and some in the silk flower section.

Generally, the styofoam in the craft section (white) and that in the floral (green) are an open cell florist foam. I actually prefer it for all of my cake dummies, wedges, etc. because I find it easier to carve and to fix if divots arise.

The dummies and wedges you order online are generally pebble styrofoam. It's "spongy" and it can be hard to carve, sand, and shape.

If I were making my own wedges, I'd do it with the floral foam.

JMHO
Rae