I haven't seen the western version of The Grudge because I've heard that it's awful, but I have see Ju-On and it isn't very good. It uses the same tactics as The Ring to create panic/scaredy-pantsness, and The Ring is much better if you're looking for that kind of horror movie (I'm talking of the western version of The Ring, not the Japanese original, which is worse). It could be that I think Ju-On is bad because I couldn't keep track of new characters whenever there was an entirely new scene in an entirely new time for most of the movie, but I'm pretty sure it's just a not-great horror movie. The very very last scene right before the credits with the chick in the attic was kinda creepy, though.