I saw most of the episodes of RMFTM as a teenager on "Cliffhanger Theater" running after midnight on a local station some years ago, and then again when Mystery Science Theatre riffed on it in the early 90's. Time has not been kind to it.
I can certainly make allowances for the special effects, which were quite impressive for a low budget 50's serial (IMO Commando Cody's flying scenes were better than George Reeves/Superman's in his TV show). And I can also make allowances for the ahem, "acting", and fight choreography -. except for the guy who plays the ruler of the Moon Men. He is incredibly miscast. He looks and acts like the fellow who comes to fix your plumbing, not the despotic ruler of an alien race. Even the corny dialog works all right - everyone rattles off their lines like strings of firecrackers, with no wasted time or pauses for things like "thought" or "introspection". Since everyone does this, the viewer finds it immersive after awhile, and even to my modern sensibilities, it doesn't bother much.
What really irritates me is the writing and the plotting. I'm not talking about the sunny weather on the moon, or baking soda powered rocket ships, or a flying suit that has controls labeled "up/down" and "fast/slow". I'm not even bothered by the cheesiness of the resolutions to the cliffhangers that end each chapter. I'm talking about the fact that our supposed heroes are dumber than fence posts and have no cumulative memory. And by the fact that although that the dialog clips along like an express train, the plot goes through the same motions again and again.
Dig it: Commando Cody and his pal are the spearhead of a top secret hi tech science lab charged with protecting Earth (or at least the USA) against an insidious alien invasion. But his office has no guards or security checkpoints. They don't even have locks on the front doors. So the bad guys walk RIGHT IN and beat the crap out of the Cody and his staff ...not once (perhaps understandable) but SEVERAL times. They even kidnap his female assistant on the second try. And they never get any smarter. To further prove my point, allow me to point out the way that Cody jumps in his flying suit and flies around getting into trouble and never actually seems to succeed in catching anyone. He does this over and over and over. Cody also flies his ship to the Moon (the woman assistant comes along to cook), stays for about 30 seconds and immediately turns around and comes back. Cody captures one of the Atomic Ray guns...and immediately loses it again to the bad guys because he couldn't be bothered to lock it up. And so on.
And you would think that if Cody's efforts were so vital to saving the USA from the Moon Men, that he might ask for a few soldiers with carbines, a few helicopters and a tank or two to back him up, instead of just working with the local police all the time. This was supposed to be a military operation, but they act like it's another episode of "Gangbusters".
It's all rather hard to stomach. I appreciate that the creators were severely limited in the scope of their story by budget and time constraints...and I appreciate that Cody is actually a reasonably tough hombre (even though he loses half of his fistfights). But I just can't help yelling "DOOR! LOCK THE DOOOOR!!" when the gangsters simply walk into his lab, or try to blow up the ship and there are NO security measures at the landing site in place...not even a fence (!).
Still, it's OK. Of the three Republic serials I've watched, "Phantom Creeps" had a better plot, and "Undersea Kingdom" had more atmosphere (hah!) and a better hero than "Radar Men", but it's an OK time-waster.
BTW...why "Radar" men? They didn't use radar, they used Atomic Ray Guns. Shouldn't the title have been "Atomic Ray Gun Men From The Moon?"
