I'm not interested in Harry Potter so I skipped that one, but I tried giving Suzumiya Haruhi no Index a try.

I'm having trouble reading it because of all the punctuation errors. There are some other grammatical errors, but those are few compared to the missing commas, periods, and the like.

I know perfect grammar is not a necessity in writing, but if the first chapter has so many errors, it raises the question of whether the rest of the story is worth reading.

What makes this "very fantastic"? If you could tempt me more, I might give it another try. I like both shows in the crossover, so it shouldn't take much.