I ordered a 997 Cab (April build) in GT Silver with Stone interior and roof. I was considering Seal Grey, but after seeing the color in person, I was amazed how great it looked. IMO, it was definately worth the upcharge over standard metallic paint, although I probably won't feel this way when I sell the car and brings nothing back!
Good point...i chose the arctic silver over GT silver because i thought there was'nt enough difference to justify an extra Pounds1,000. I noticed that sometimes arctic silver looked either seal grey or GT silver in certain light conditions!
I went with the Artic as well. I love the way the Artic has more reflective qualities under the sun. Originally I had picked GT Silver and was lucky enough to find a dealer with an Artic 997 and a GT Silver next to one another outside. The GT is really,really nice but the Artic is a lot deeper... You can't go wrong with either one.