It's a pretty solid series. The anime is meh and I haven't played much of the VNs but the manga is very well done. I would definitely recommend the manga over the anime, it's more suspenseful and scarier. The anime doesn't always get the atmosphere right and the animation is subpar. Very good series though. Umineko no Naku Koro Ni is also quite good, although it's focus is much more on the mystery and supernatural aspects than the horror.