The glow engine purists are wrong headed to say the least. This hobby started with spark ignition gassers, which were heavy and underpowered. Then came this new alcohol based fuel, also ignited by sparks at the time, that gave the engines more power. It wasn't any more proper than gas for models; it just gave them more power. The glow plug made them lighter, and nitromethane made them more powerful. Glow engines aren't traditional or more pure than anything else. They were simply the best option for powering mid to large size planes for about 30 years. If Chuck Cunningham or Joe Bridi had had DLE .30 engines I'm sure they would have used them and loved them. Ditto for lipos and brushless outrunners. But they didn't, so they used the best power system they had at the time. The expectation then was that something better would come along and displace glow engines. It's sad to me to see modelers criticizing other modelers for being a part of that natural process.
And while I'm on the topic, when did this hobby become about preserving the past? Sure, there is a heritage to aeromodeling that I appreciate. But the impression I get is that in the glory days of the 60's and 70's modelers were all about innovation and embracing new technologies. That's what made it exciting. Those same people now say that if you are flying something developed in the last 20 years you aren't a real modeler. I say the old heads who are hung up on tradition aren't real aeromodeling hobbyists. It's a much bigger honor to our heritage to continue innovating and exploring new technologies like they did in the "glory days" than to sit around complaining about what's new. Myself, I appreciate all of it. I fly a classic pattern plane that is glow powered because that's the best choice for performance, I fly a modern Sukhoi 26 that uses a modern CDI ignition gasser, and I fly an EDF F16 among others. None of my planes are state of the art today, but they all were the newest thing at one time. We are far too small a group with too many difficulties facing us to divide over something as silly as tradition.