The bottom line is you want to ask the manufacture of the product you want to buy if it is acceptable for over radiant flooring systems. Anything other than that is just guess work from everyone else. The manufacture will give you a definite yes or no.

That said, I wouldn't really recommend it. I've done a laminate floor over heat that was cleared by the manufacture, but there isn't much thermal mass there. The floor got warm but it didn't really feel warm.

The benefit with a tile floor is that while it takes a while to heat up, it holds the heat. When you walk on it, the floor feels warm. If you put cold wet shoes on a vinyl floor,they will suck out all of the heat in the area and the floor won't turn on unless the sensor is in that area.

That's just my personal opinion. I'm not saying it's wrong but it depends on what you expect to get out of it. You might be just as well off wiring an electric heater on the wall and calling it a day.