I really like the silver and the blue. I really wanted Cosmic Blue or Sunlight Silver when I first started looking, with CB being my first choice. There were no CB available in GT w/o nav, so I went with the silver. Looking back, it was a great choice. The silver has really grown on me, it is an awesome color. Nice and sleeper, doesn't show dirt badly, etc.
I wished that Mazda would have offered a darker hue of blue, and orange. I have seen a couple of the orange 3s, and its a really good looking color on there.