I do agree with John and the on board shown is not modern at all, it's how we did things before the industry decided to come out with different types as electronics got better. Every once in a while I will still make one up for someone like that, I find my home mades are better then the store bought. It's just a micro switch that goes on and off with throttle servo contact and you can set it {program it} so it goes on and off any place you like. No electronics to poop out on you! I agree with John that on board systems are not required in most cases, a well tuned and set up engine doesn't require them. I did try to install one of the Expert systema in my pattern plane but it was because of the cowl being in the way of my inverted engine. The Expert was a junker and only worked once in a while and if it was real close to the engine so I just installed a remote glow driver. {home made} The engine is tuned well and set up correctly so as of this date I have had no dead sticks at all. A required item?? Nope but they are sometimes a nice thing to have, just not very often. I see too many of them having problems at the field.
I do like my power panel though. As john mentioned not something required but I still like it. All mine is used for is the electric fuel pump installed inside my flight box. This time of year I can get a bit more juice to the glow plud then my glow stick puts out, that helps a lot with some of my long wired remote glow drivers but that's about it. I could do away with it and not miss it at all but I'm set up with one and like it.