Once in awhile they will have a good (unique series). I would say 2/3 months it's worth it, but there are months that go by with nothing worthy of having a membership.
Given that I said 2/3, so 66% of the time it's worth it. So yes, in that sense it is!
It's relatively cheap also.
Since it's not really a committed subscription, I think it's worth it too. I don't care much about new series but I am mostly watching older series or series I am genuinely curious about.