The fiberglass mesh is easier to work with, but a little pricey. I think you should probably use 'concrete bonder' (white glue) to wet the wall and make sure the rough coat layer will stick. Another variation is put some color on the drywall, and then patches of wax, like furniture wax, then the finish coat in a different color, the waxed areas will flake away, given the look of an ancient, distressed look plaster wall.
If the wall is to be wavey, make sure you don't use any gloss type treatments.
Sometimes for this effect you combine plaster and drywall compound about 50/50 - much harder than drywall compound on its own but it sets faster. Nothing trowels as nicely as lime though. The drywall compound/mud is basically white glue and cheap filler.