I've been mainlining kaiju films since a kid. But there's only so many. I've got all the Godzilla/Toho tokusatsu films. Got all the Gamera films and oddball films like The Last Dinosaur. With 100s or 1000s of spaghetti westerns, giallo, martial arts and Eurocrime films, it just seems like the well for Japanese Giant monster is so, so shallow.
I've never been a fan of Ultraman, just never captivated me and with the amount I spend on Godzilla stuff it's probably for the better. This week I picked up Ultra Q(1966) on dvd from Shout Factory. It's been out for a few years and it's fantastic. Try to picture a 30 minute Twilight Zone/Outer Limits episode with a giant monster in it, by the same people who did the SFX for the Godzilla films in the 1960s.
If you are a kaiju fan this is essential viewing, from a historical perspective and it's just a hell of a lot of fun,