PAG oils are basically the same. The difference is the viscosity 46, 100, 150. Personally, I wouldn't mix them. Use the one the compressor requires. I have found that doing AC work, there are no shortcuts.
You would need to look at the density on each products from their respective SDS's. There are water soluble PAG's (heavier than water) and water insoluble PAG's (lighter than water). The densities are quite different and they are not compatible. Mixing viscosities of like materials are not typically an issue. The typical issue if you mix like products would be foam.