herbfargus: I was looking at the control block, but when I did it was temporarily out of stock. It also has a lot of functionality that I will never use with my NES only system. Besides, I have lots of electronic components on hand to build my own power control circuit and I want to be able to say that I built it myself (even though all the coding is already available).
w3ace: I haven’t seen anything written about risk of damage. I checked through the gamecon readme and the only mention I have found is that the raspberry can supply enough current to run four controllers. That’s two more than I will ever use. The circuitry is just a CMOS parallel to serial shift register which isn’t particularly fragile.