As for wood, acoustically, MDF is great. It's made of dust from many fibers bound with glue, so it's inherently non-resonant. But it's not very durable as a piece of furniture. Even if you never get it wet, in humid environments the wood will swell enough that butt joints will show through veneer - you'll see the seams. I think MDF is better acoustically than the best plywood, but it's heavier and less durable. I'd never build a basshorn out of it because of that, but if you use the right joints, it makes a good home hifi speaker.