Power Metal is one wierd genre. It seems that even if you and someone share a common opinion on 10 PM bands, it's unlikely you'll agree on the 11th. Because there's so few variations within the genre's sound, people tend to latch onto very specific components of a band; vocals, guitar tone, subject matter, etc. They either love or hate bands based on, what would seem to outsiders, the most subtle of nuances.
I felt that the crème de la crème of Power Metal was Iced Earth. However, even though the songwriting quality didn't drop when Barlow left, the band lost a lot of its personality. Brainstorm was a band that seemed to have a bright future. However, on recent discs their sound has moved in a more generic direction, which I don't care for.
Of all the bands out there, I think Tad Morose and Pyramaze (aside from the aforementioned Angra) are among the genre's finest. Can either band break out beyond where they are today? Hard to say.
Zod
P.S. - if you consider Nevermore to be Power Metal (which some people strangely do) than all conversation about all other bands is unnecessary.