I don't have much knowledge of Hellsing other than having watched a few of the original anime series a few years ago.
This revamped version certainly looks a lot better than the original. It might be pretty dark but we get lots of details and some very slick animation. The 5.1 sound is pin sharp and is an acoustic treat which compliments the action scenes - and there are plenty of those ...with plenty of splattering.
Although there's lots of gore and violence, this isn't a mindless series. This is as much a series of politics and religion as it is a vampire story. With references to the Vatican, Protestantism, and soldiers of God - it's clear that this has the potential to become something more than just a slash 'em up.
If you're a fan of the original manga series, or the other anime series, then I'm sure that you'll love this as you'll already know the characters.
However - if you're new to this, then this introduction to the Hellsing Ultimate contains little plot and the characters don't feel very developed. I'm sure that as the series progresses the characters will gain more depth, but the first volume just feels a bit flat.
The voice acting in the English dub is overall pretty good, but Integra Hellsing always sounds a bit bored! I always prefer to listen to the original language soundtrack through, and in this case if you stick to the Japanese soundtrack with subtitles the series has a bit more life.
In a nutshell: Series such as Guyver - The Bioboosted Armour Vol.1 [2007
] have breathed new life and energy into some modern classic series. This tries to do the same, and though Hellsing Ultimate does give a great snazzy new look to Hellsing whilst remaining true to what has already been established, it relies too much on the audience knowing the characters in order to actually feel anything for them.