Zbrush has a unusual 3d context. It's not displaying polygons like any other program. So it complains because of that. The problem with any polygon that isn't a tri is that you have to convert to a triangle to display it. This doesn't matter if the polygon is planar but if you have a non-planar polygon it can have several…
Yes, quads are easier to work with. Easier selection/control of edgeloops. UV unwrapping is easier. Rigging is a LOT easier. Meshes deform better(game characters are still ultimately triangles though) But all quads are 2xtriangles anyway. It's just that the edge that bisects the quad is a hidden edge. Real-time engines do…
- well placed triangles help you keep control the flow and silhouette of your mesh. USE BOTH! - quads are easier to edit around, create loops and whatnot. USE BOTH! - your in engine vertex count (don't trust max or maya). triangle count gives you an idea, poly count is useless - everything becomes triangles in the end…