I have a professionally installed electric Holl/Webb "moon-roof" in my VX and I simply cannot imagine having a VX without it. It was $1500 worth of money well spent by the previous owner.

As far as a rear-seat moon-roof, I'd say forget it. Besides the major installation headaches due to the structural integrity of the VX's roof support and resulting high dollar cost, the major problem for rear-seat passengers if the lacking side/outward visibility due to the massive C-pillar. The huge C-pillar of the VX is smack dab in the way of any outward side visibility and makes rear-seat passengers feel like they are in a cacoon with tunnel vision forced to look over/around the heads of the front-seat people and out the windshield (not good). Consequently, the rear-seat situation is not ideal for transporting people IMHO, and thus removing the rear-seat altogether is the best option for many VX'ers by making it strictly a front 2-seater vehicle.