This is not a sequel to the movie. In fact it is more of a reimagineering. The overall premise is the same but they are also many differences.
The quality of the episodes varies from mediocre (most) to good (some) and even up to great (a few). I'm not sure if I would categorise it as cult or a classic but aside from one really bad episode they are all entertaining in the 70s kind of way. You need to be able to ignore the logical flaws and scriptholes (which I couldn't always). Ultimately it is generic scifi stories where the connection to "Logan's Run" didn't really matter.
If you're a fan of 70s scifi I suggest to give this a try. It doesn't take long to finish. I do understand though while it got cancelled. After Star Wars showed what scifi could do this felt like from a decade ago. And even then there already was Star Trek (interestingly there are some people that worked at Trek on this show) which was a lot more sophisticated.