Dynamic material quick question

I would like to know if is better to use TexCoord instead of Panner?

What practice is better - use texture param or two textures inside material and scalar parameter for selection?

I wonder if game performance can suffer because of many dynamic materials?
Should I avoid some calculations inside materials?

This should do exactly what you need. Multiple parameters shouldn’t really cause performance to suffer on their own, it really depends on what you are doing in the material. In any case, see the image below. You can easily parameterize U and V scrolling speed on textures using this method.