A very good slow burn! As a Catholic and a big fan of any vampire media, I thoroughly enjoyed it. Plot is basically a devout priest meets an "angel" and revelation-like chaos ensues.
The acting was amazing, and the character development relatively good. True, there were some bits of the show I had to roll my eyes at, but I still think it was a good representation of the horrible possibilities any religion can face when misled. I guessed some parts early but it still had me hooked. :)
And yes, some of these reviews talk about the interpretation of Catholicism and other religions in the show being biased (leaning towards Christianity=bad). You'll just have to take it with a grain of salt. If everything and everyone was perfect, there wouldn't be a show! And even with that, I think the whole show makes for good commentary on religion, it's purpose, and atheism. Anyways, it's an enjoyable watch!
P.S.
I'd have to imagine me being Catholic made the slow burn/dialogue more enjoyable. If you're not interested in listening to a Mass or long Bible quotes, it might bore you.