More cabs are made from MDF board than any other material and way too heavy... Whoever came up with the idea to start building cabs from this material to cut costs needs their ass kicked.
I would rather have a pine plywood box over Particle board for covered cabinets Chip board would be perferrable over Particle board IMO.
the type of material the cab is made of does not have much bearing of the sound quality of the cab; How the cab is condtructed for its intended aplication is much more inportant than the wood selection.
if I was not going to cover the cab I would perferr a Birch cabinet because of the higher quality of the top veneer, other than that I don'[t really care as long as it is not made from that heavy ass MDF board.
as far as the OP question... Avatar cabs are of some of the best built and best sounding cabs on the planet and very reasonably priced, JMO.