Sleep sheep opinions

So I bought this sheep at hallmark. Mine is a little different but the same concept. It has the sound of the mother's heartbeat, rain, ocean, and whale songs. It hooks to the crib or whatever you are using. There's a timer on it for the sounds and a sensor for if the baby makes a noise the sounds turn back on. The sound box is removable so the baby can play with the sheep too. I'm just wondering if anyone has ever used anything like this and how they liked it? I paid $35ish for it and am hoping it isn't a waste of money!