Yes, the G-code shows numbers from S180 down to S0, so it appears to be sending varying power values.
When running at higher speeds like 1000 and power 0-255, I get black anywhere there is color. And if its slower its just blacker.
I've tried so many settings from slow to fast, and max power down to 170.
When I run it really fast, at a speed of 3000, and a lower power, it almost resembles greyscale, but its blurring.
Here are a few test burns to see what I'm getting, which to me all appears black and white, not greyscale.