Considering in the actual game, the regular humans can't even see over the dashboard? I'd say it's pretty close. ;D
Since it's based on a slightly SD "RC" model, the frame is higher off the ground, the tires are bigger and the turret is bigger than they should be, but not by much. The hog is stupidly oversized in the Halo universe. It definitely suffers from Destroid syndrome though. Just because it's technically in-scale to the home universe doesn't make my 1/160 Warhammers not-too-small or the Warthog not-too-big for what it should be in Battletech.
Still, I would hurry out and grab a couple while the wave is fresh if you are inclined to. Prices are already getting crazy on ebay.