I have fewer than half my teeth left and plan to get a bunch of crowns/bridge work done. The dentist plans to use ALL Porcelain-fused-to-metal crowns, so that everything is consistent/symmetrical/predictable. I asked about using all-porcelain in the front-top teeth and metal in the back, but he said that the metal-infused ones will look darker when the sun hits then vs. the porcelain in the front that will allow more light to pass through. Is this a VERY noticeable difference?