Hi, klamb17!! This is my experience with specifically the black Wilton spray: On May of last year I made a Michael Jackson cake for my son, and since I was not looking forward to tint the MMF to black I decided to use the Wilton spray and to make sure I had enough color I bought 3 canisters of black. You can look at the cake in my gallery, it never turned black
I was panicking but the cake was saved because I remember I had black sugar, which I use to cover the 10in cake .
You can still see the gray under the black sugar, my son did not notice!!
He loved his cake (he still is a Michael Jackson fan)
Now if you can get your hands on an airspray machine that would be awesome!!!