Most of the time, i will cast my inclusions from the same resin I use for the dice.
I did do a test (300 rolls for each die, plotted) for the first set i did with wood. While a very small sample size, I didn't find anything outside the norm (I have a spreadsheet graph from a previous set of clear resin with 500 rolls).
While I wouldn't say they are balanced, I would say that most dice i make are perfectly fine for friendly tables.
