I watched the first three episodes of this anime on a whim, mostly as a result of the "three episode rule" which is mostly bull shit. After watching them, though, I was convinced that this show was a 10 and would quickly become a personal favorite.
Though the beginning of this show is golden, everything in the show takes a complete nosedive after the eighteenth or nineteenth episode. Hideaki Anno leaving the show only works towards its detriment. However, the final episode is quite nice. I would suggest skipping some of the later episodes if you enjoyed the manga, but the rest is very high quality.