>>714150283
Ring of Sacrifice has a specific use case, which is to scout out new areas before deciding whether to take them on now or once you've levelled up some more. I found it especially handy for the climb down the Tomb of Giants, because I could map out the darkened areas and memorize enemy placements without fear of losing all my souls after inevitably falling off or getting killed by the skeletons.
>it could be a huge disadvantage since all the rings are so powerful
This could be said about any ring in the game. The trade-off of wearing the RoS is effectively being weaker, but not having to worry about losing your souls and running back to your bloodstain.
>>714150449
There's one on a corpse on the aqueduct by Firelink Shrine, and the vendor that appears in the first bell tower after beating the gargoyles sells them for 5k souls each. There's also a couple Rare Rings of Sacrifice in some of the late game areas, which have pretty much the same effect. I'd be more impressed if you didn't manage to find one of these in your playthrough. Then again you're just a shitter who has never played the game.