So I've bought 4 ultradiscs at this point, two i bought at REI, the other two off amazon.
-if you're looking for a product made in the US, this is it
-if you're looking for a disc with an good balance of control, speed, and distance, this is it
-if you're looking for a disc that will last you for a good 5 years or (probably) more, so long as you don't chuck it at cement, trees or rooftops, this is it.
the first disc I bought got roofed a few years back, and since then I needed a new disc, I considered whamoo, but found their discs were super flimsy and when I've tossed them they have way too much float for my taste.
later I found the nite glow disc, and bought it of amazon, loved it, was just like my regular disc in shape/size/weight, and with age the glow improves. btw, the picture isn't exaggerated, the camera was just set at a very high film speed, I managed to get the same affect on my android phone by adjusting the ISO number to 1250.
I recently purchased the ultraviolet disc, and love it as well. again, it's the same shape/size/weight as all the other ultrastar discs. the color changes when exposed to sunlight, the higher the UV level the faster and more dramatic the change in color from white to purple (in low UV conditions, like a cloudy day the disc may only turn a light pink color). when changing it back to white, it changes a lot faster when put in absolute darkness rather than just putting it in the shade.
the only color i don't recommend is black, because on a hot summer day, the sunlight will actually cause the plastic of the disc to soften, thus allowing the disc to lose it's shape. My sister had a black disc, and although it looked cool, it was not good to leave it out in the sun.