if anything it could be good for practice, i wouldn't personally use it, i doubt it'll sound bad at low volumes, i would turn it up too loud, with my xxx 15s I have double baffled 3/4 MDF and when i crank it the wood flexes some aweful, I couldn't imagine what particle board would do.
I wouldn't bother carpeting it, when it goes throw it away build yourself something solid and just consider it a good learning experience. A+ for craftsmanship, those cuts don't look bad at all considering its p-board.