Practice heads and opacity

Okay, so. I have a practice head with an extra "skin" and a square of practice "skin". Of course I test designs on them but everything always ends up kinda streaky and never opaque. This is no matter how much I load the brushes, btw.
Things are fine on skin but I can't continually test them on myself and want to see if I can get the paints to the point where they are a more accurate representation on the head.

Do you think I'm doing something wrong, and if so what are your suggestions for correcting it?
Or is this one of the pitfalls of the practice heads (like the staining)?

I think that it is normal. I have the same problem.

That is normal. Natural human skin is an absorbent organ that has pores and such to keep the moisture balance. Manufacturers of face paints take this into acount when they make the paints, so the paints wont work the same on a synthetic rubberized plastic. You aren't doing anything wrong.

Think of it this way, have you ever used a sharpie on a peice of posterboard to make a sign? You probably used the non-shiny and smooth side, didn't you? That's because that side is like the rubberized plastic and the ink and pigment can't absorb into the paper on that side because of that super smooth and shiney barrier. However, on the side that isn't super smooth and shiny and more like normal paper, you can write, draw, and color with no problems with that sharpie. That's because the paper on that side has no barrier and is more porous which allows the ink and pigment to be absorbed into the paper. It's the same way with the practice heads and our own skin.

Hope this helps and made sense.

Nope nothing wrong.

I have had a practice head for 10 yrs and used it less than 2 dozen times - until the last month in which I am using it daily. I actually have 3 now, a Mehron, a new Pro Face and one that my friend Dawn slipped into my bed in Vegas at convention. I use my Mehron head. I don't really care about staining. I clean the head to perfection every so often. And it never going to be true so nope not always opaque, not always the most crisp lines, but for laying out faces and building the memory muscle for those faces it's great.

yeah, i like my practice head for the ease of painting on it and not on myself, but its just not the same.... especially for blending..