I've added the S/812 to my SabrinaX driven by the Gryphon Diablo 300 and as another user said, it just adds so much more than bass. I think the changes in soundstage are the most satisfying ones. Any speaker in any price range can benefit from that, given that the room has proper treatment / measurement / acoustics.
By the way I am letting my pair of SabrinasX go, less than 1 year old. If anyone is interested, here's the link.