Thanks fish lover0591, I can assure you the base is extremely stable, you must remember it is built out of 18mm (3/4 inch) chipboard and has ample screws holding it together. Also the back panel is situated inside the top sides and bottom panels which gives it its stability. It doesent move at all, I made sure the measurments were all exact so it fitted together perfectly.
Co2 system cost £199.99 (£265 RRP) and they threw in another 500g cylinder, which was nice !!