For me, even all these years later, when we have pretty much all the films available in some home media format, the ones that were hardest for me to find and watch are the ones I appreciate the most. This was certainly the case with Smog Monster. I saw it once when I was 4 on TV, and that was in 1980, and I don't even know if I saw the whole movie. All I remembered was the scene where Hedorah's ooze was covering the car the two main characters were in, and hedorah's flying form (I thought that was his nly/main form for about a decade), then 10 years later, in 1990, I finally saw it for rent at Blockbuster. In fact this was one of 4 films (The others being Gamera, Gamera vs Guiron and Monster form a Prehistoric Planet), that we made an elaborate plan to rent all in one day, daisy chain our VCR's together, and record them to make copies for ourselves.
G vs. The Smog Monster is up there for me with Destroy All Monsters as both of these were the last G films I saw as a kid since they were seemingly never on TV in the 1980's. Of course they did both show up in the mid 90's on sci-fi channel, and on home video shortly thereafter, but of course those were the Toho International dubs. thankfully the Orion VHS (which I own) of Smog Monster has the AIP dub, and before MB offered their *butchered* AIP of DAM, I got it on VHS from a friend off of a TV broadcast from many years ago.
There are no more good TV Shows, only ones that haven't disappointed me yet.