You can still get higher-grade cultured bioware, but it's still cultured for you specifically no matter what the level.
And Ympulse, I have to ask: "as in non-alpha, beta, etc", where is that in the RAW? Isn't that just Standard, or does Augmentation use Basic instead of Standard? And where they use Basic, how do you know it counts as Standard and not as non-Cultured?
You claim it's a houserule but honestly reading it, it doesn't strike me as a houserule. So since there are indeed disagreements over, I need an argued picture, not a mere statement. Also, please don't act as if I'm a bad GM for wanting this clarified. I don't even have a single player using this right now, my own character concept is the only one using it.
Edit: I should note that character concept aims for development into ~2.5 essence worth of basic bioware with Type O System, at a monetary cost of >300k nuyen instead of >3m, so which heavily benefits from those 30 BP.