The Best of Japanese Science Fiction

I bought this book cos I'd never seen any Japanese science fiction. The stories didn't do a whole lot for me. They tended to be simple stories about a strange premise about the future, like a future were a fascist state takes offending humans and, through some unknown process, plants them in the ground where they gradually turn into trees. I don't know whether the inability of these stories to really grab my attention is related to the translation process, but I suspect not. My reason? "The Savage Mouth", a gruesome story by Sakyo Komatsu, which gripped me. Unfortunately, it gripped me right in the stomach, and I almost lost my lunch. Read it, but don't say I didn't warn you.
The collection doesn't even do much for me as a cultural study. The stories don't seem "Japanese" to me, they just seem mediocre.