I'm not very familiar with Manowar. I remember hearing about them a lot in the past, being mention on a Maiden board i believe. I was getting the impression that Manowar are consider as great and legendary as Maiden by some. I never thought of them as power metal, but then again i have yet to hear them!
And Hansi Kursch is an awesome vocalist! I'm watching BGs 2011 Wacken show right now. I really love his vocals and style, i just wish BG strayed from the fantasy stuff. I'v never listened to Angels and Demons. Sound like it's fantasy stuff though, am i right? But i think i'm still gonna give Blind Guardian another chance, as i have some of their music available to listen in my car and i have a driving job.
A lot of people assume lots of these power metal bands are hugely influenced by Helloween. And that may be true for a lot actually, but i remember reading a quote by Blind Guardian saying they were never influenced by them. And i'm not surprised really, i'm not sure BG ever purposely meant to become a "Power Metal" band when i look at their history. Seems like they started out as a thrash metal band, then evolved into having a more symphonic sound, but still wanted to make thrash/speed metal as it's in their nature, and voila! They sound like Power Metal! And of course no thrash band writes shit about elves and wizards and magic fuckin spells..
to close this rant, i just want to state how much a hate that so many people ignore newer Helloween! There are tribute albums that only have Kiske-era songs. When people talk about Helloween being the originators of power metal, i always wonder if they're also talking about the post-pink bubbles stuff too. With Deris they have done some amazing stuff, for the genre too! Plus, Kiske hated Helloween too. People talk about him coming back being so great, but he never respected what the band was doing.