Quads are fine, triangles are fine unless the interrupt needed edge low/quad loops.
quads, tris, and ngons are fine if all you're doing is rendering "concepts" where you're expected to create models and renders quickly (aka "dirty" modeling, see Vitaly Bulgarov) and will do clean up in post.
Quads and tris are ideal for game models and baking. Some engines and baking programs just won't work with ngons.
Quads are ideal for animation/deforming because they behave "expectedly".