I bought some Flamboyant Blue paint from Wrights of Lymme and went straight into painting my sign. I was shocked to see that the paint was nothing like any of the One Shot paints I had previously used. Rather than being opaque, this paint is translucent.
Always, alway, always check before you jump right in. I wouldn't say I am displeased with the effect it has given me, I was just expecting something different. It looks more like a stained glass window effect now.
Oh well, it's a happy accident. I might try and do another coat to try and even things up a bit.