One added problem will come from directionality of the RF signal from and o the handset, especially when the device is being held in the hand, and near the body(which has natural capacitive effects) that will impede the RF signals.
At the end of the day, your sound is all coming from one spot, so directionality isn't going to quite match a for-realsie surround sound setup, and the system we listened to was a little sharp in the high end, but it's certainly a unique and appealing offering from Mitsu to the everyman TV watcher.