I mostly use unwaxed plastic foundation in wooden frames. I collect and save my wax and paint it on the frames much thicker than the commercial coating. My wax contains only the chemicals and contaminants my bees bring home rather than the mix present in all commercially produced wax. I can't say what the plastic itself puts out. I am at a point where I am going to be taking some of my older comb out of use. With the plastic foundation, I can scrape the old comb off, re-coat the plastic foundation, and give it back to the bees to draw out again.
I have just purchased some wired wax foundation to get drawn out. I plan to use it on nucs where I am trying to get queen cells made to put into other hives and raise some queens. While I like my plastic foundation, especially for extracting honey without having to wire frames, I do not like the idea of having to use tin snips to cut queen cells from my plastic foundation for transplant.
Most of the plastic foundation I have is not black, but the black does make spotting eggs easier.
In my long winded way, I guess I am saying think about what you want to start with and why. As the years go by, thanks to L. L. Langstroth and commercial standardization of frame sizes, you can buy and use other types of frames or foundation for specific purposes. I've never had a hive explode because I mixed plastic foundation with wax foundation, and the bees have never filed a grievance.