I think the real secret of this Card is you are spending the XP not for the extra ability but for the access. I am less interested in this card as an "UPGRADE" than as a good boost to willpower and sanity buff. For Roland, this is almost a auto include. I often upgrade to Elder Sign Amulet with him or Mark and this is just better across the board. The extra willpower helps to protect them from the encounter the deck and the sanity boost is well worth the cost.
Item. Charm. Blessed.
You get +1 .
After you succeed at a test on a treachery, exhaust Holy Rosary: Add 2 tokens to the chaos bag.
Whoa! I think this is the first time we've seen a card positively change class from one version to another (I'm not counting the dual class cards or the new upgraded cantrips). So, if you're a guardian who has been casting longing eyes on the Holy Rosary since the Core Set, you can now have your very own, and it's better.
But really, how much better? I'm a little skeptical that this thing is going to fire more than a couple times a scenario, even if you have it in your opening hand. Most turns, you won't see a test on an encounter card. And even when you do, you might not pass it. Of course, there are ways to meddle with the encounter deck so that you see more of these tests, including in the pool. "Let me handle this!" and First Watch come to mind. But on the whole, it seems like a pretty iffy way to add more tokens to the bag. For me, this would be a late-campaign upgrade for a Sister Mary deck, when I'm sitting on a bunch of xp and there's nothing in my deck I want to get rid of. In that case, sure, pimp my rosary (apologies to all Catholics).
I will say that this card may make sense in one campaign: The Circle Undone. That hexy hellride is FULL of treacheries with checks. I just checked -- in the deluxe boy and the 6 mythos packs, here's the breakdown:
checks: 4 cards checks: 4 cards checks: 40 cards
So, yeah, you'll be taking some checks. Static buffs of any kind are advised -- all the better if they reward success. Who knows? Maybe you'll run across a certain traumatised chef in the course of your adventures, in which case you can get paid twice!