It seems to me that I have a habit of playing, and occasionally reviewing nsfw visual novels...
It's usually a "I came for the lewds, stayed for the story" scenario. The best (in my opinion) are in that collection. Are they the best because of their story? Characters? H-scenes? Nope! It's everything combined! They are all amazing in every field!
If you want a more in-depth view of my opinions click on the actual title of the collection and read the little blurbs I have.