Yeah the monsters looked really bad, which I think was because of the low budget and short prep time (because the script was always being re-written at the last minute) and maybe a bad or just average special effects department. But the range of monsters they featured on the show and the lore about them was pretty well done I think.

But Darren McGavin and Simon Oakland and the rest of the regular cast were great. The opening whistle from the show's theme music always makes me feel happy. Never thought about it before, but your Hellmouth theory sounds great. Maybe Nikki Wood had some adventures there :)

I hoping that because my cousin was a fan of sci-fi movies and tv he might warm to the idea, but no dice :)