I'm all for using whatever you want (like I said, the dice I prefer get lots of questioning looks). But I'm just pointing out that there is no way to get a truly random chance on any dice. Yes, it may be more balanced than others, but even Casino dice could have imperfections. That imperfection may be that out of 1000 rolls, it comes up one 170 times instead of the predicted 167.
My preference is to not worry so much about how "right" the dice may be, just that they aren't obviously wrong.