IMO, painting can be both easier and more difficult, depending on what you are trying to achieve. If you just want a passable flat black finish that looks decent from a few yards away, that’s relatively easy. If you want to have a nice smooth, uniform finish on MDF that still looks professional when you’re right up next to it, though, that will take much more work. When you’re painting something smooth like MDF, keep in mind that even something as seemingly minor as slight differences in the evenness of your sanding will be visible through the paint. There’s nowhere to hide... the surface must be SMOOTH and UNIFORM to look that way when the paint goes on. In my experience, the paint ain’t gonna hide it.