Bad when you play it and do something other than trash, as it puts you down a card on your current turn for either nothing or, at best, an extra useful card next turn, making it a wash. But if you do play it and trash, then that's quite good. It could be a good opener, since most of what you're liable to turn up with it will be something you'd want to trash.
Still, even as an opener, the benefit would be slow to manifest itself, so except on a slow board you probably need to have a use for the reaction effect for the card to be worthwhile often. And it's not good enough to trigger the reaction from other copies of this card. Why? With two copies in your hand, you play one, trash the top card, use the second copy to put it in your hand instead of the trash, and presto -- you've successfully pieced together a cantrip! And all it cost you was a card slot for that second copy that's still eating up a slot in your hand.
So you need a separate trashing effect to use this. But if you've got that, it could be great. Trash-for-benefit cards like Apprentice, Salvager, and Remodel may be used on power cards and Provinces without sacrificing them. Sweet stuff. Also, you're immune to trashing attacks, which wind up helping you rather than hurting you -- but for that reason, your opponents will probably avoid trashing attacks when this is around, in which case you don't need this after all.
What about non-for-benefit trashers? Loan and Lookout will each put a card in your hand, but those combos aren't much better (if at all) from cantrips. Reacting to trash-from-hand (Chapel, Steward) is basically useless, since you're just undoing what they do.
So I think this will be a pretty situational card. You need either trash-for-benefit cards or a slow board with little or no other trashing. I think there are probably enough of those kinds of boards to justify the card (certainly there are narrower official cards), but you have to expect it'll stay on the table a lot of the time.
