Okay I watched this through once without knowing that this was the QC test, so I wasn't paying much attention to the details, was just busy getting blown away by the animation and how closely the thing follows the Hellsing manga.  I'm typing this as I watch it a second time.  The first time I did notice that the encoding gets nasty in a few places.  I'll only say that once since I'm not sure about any applicable technical restrictions at hand.  It's obvious when it gets messy so I doubt it's useful for me to point out where exactly.  

First thing in this second watching:  This is merely an opinion, but I'm used to Integral being called "Sir".  Every fansub of the Hellsing TV show that I saw had her title as "Sir", even among the variations of "Alucard/Arucard" and "Seras/Celes" etc.  It really doesn't make that much of a difference, but it's almost part of the show's charm that she's called "Sir", like in Star Trek or what have you.  

"Such rubbish"  I talked to an English friend of mine who I often run things by to see if they sound authentic, and he said in this situation, "Bollocks" is a safer bet.  

Another opinion thing here:  Unless it's specifically referring to the christian Antichrist in the line referring to "anti-christ monsters", it's a tad confusing to word it that way.  I'm assuming the meaning is that they are in opposition to Christ (I did hear the name articulated in the spoken dialogue), and to be fair I can't think of a better way to word it offhand.  "Christ" should be capitalized though.  

"Somewhere in that village, there's a vampire controlling those ghouls" would in my opinion be better written as "Somewhere in that village there is a vampire controlling those ghouls."

"No matter how many troops or officers you send in there, it will simply amount to feeding them" is a tad clunky, perhaps better as:  "No matter how many troops or officers you send in there, you will simply be feeding them"

"[...]and becomes a ghoul, a servant of the vampire, and nothing more" might be better as "[...]and becomes a ghoul.  A servant of the vampire and nothing more."

"All that I desire are loyal slaves." should be "All that I desire is loyal slaves. "

Three-headed Satan frozen in the ninth circle of Hell, they animated the "shooting the shit out of Alucard" bit extremely well.  Has nothing to do with fansubs but I thought I'd throw that out there.  

"As an anti-vampire expert, a human is[...]"  since every line following that one is talking about humans in plural, that line should too; it flows better, so "As an anti-vampire expert, humans are[...]"

GOGO ALUCARD GUN POSE.  Is he a badass?  Hell yes he is a badass.  

Purely opinion, but I like "Lanchester cross" better than "Lanchester crucifix."

"There's no freak alive who can take these uninjured" should be "without injury" or "without getting injured", else it sounds like he's saying they can't handle the bullets when they're uninjured.  

"Young Lady, are you a virgin?"  Okay, I know I'm an asshole to refer to official translations, I'm not dissing the work of the fan translators here, but I think the line is more badass the way they put it in the official manga translation:  "Hey Girl.  You a virgin?"  If it's more accurate the way you guys put it, crazy fine, but if it's interchangeable, I'd reccomend the second version.  Now with that said, I'm not looking at the manga anymore for this.  

Oh by the way, the way to a vampire's heart is through the lungs of a chick.  

"police girl."  NICE.  Best translation of the nickname.  However, it should be capitalized everywhere throughout the subs.  Wait, why can she see herself in the mirror?  Is that another one of those fake vampire things that they don't pay attention to in Hellsing, like going out in sunlight?  Meh, not about fansubs.  

"How does it feel, being a draculina?" would be better without the comma.  

"Of course, you will be working with us as a member of the Helling organization"  "Hellsing" is misspelled there, chief.  

"There's no way to return humans to their former state, once they've become like this."  The comma is unnecessary.  

"Sir, yes sir, my master!"  <--do you really need to sub that?  I mean it's in The English and stuff.  If they're going to be cool on us and pull out The English, we may as well not have the sub at the bottom of the screen, just unnecessarily draws the eyes downward.  

Holy shit police girl's slide looks amazing in that one shot.  

"It seems you finally understand, what it is like to be a Median."  Again, no comma is needed there.  

Haha, that initial "full of bayonets ohnoez" falling-down shot of Police Girl is directly from the manga.  

Is the first thing Priestman says just a mutter or a grunt or something that needs no translation?  

"We are the emissaries of God, the agents of the one true lord."  "Lord" should be capitalized.  

"Our goal is to annihilate those simpletons who would oppose out lord."  Again, "Lord".  

"Amen!" and every other instance of it afterward, same deal as "Sir, yes sir, my master!".  No need to sub that.  

"He was just small fry"  Shouldn't that be "He was just a small fry"?  

This entire fight is beautifully animated.  

Another appearance of a subbed "Amen!"

Yeah man, throw those bayonets.  

And again, "Amen!"

"Dust to dust" suffers from "Sir, yes sir, my master!" syndrome.  

What he says afterward; I am pretty sure he's supposed to be quoting Scripture there.  If he is, the verse is Genesis 3:19, King James Version:  

"[...]for dust thou art, and unto dust shalt thou return."

Another "Amen!"

A note here when Integral busts in:  we can hear Anderson articulate "Sir" before saying her name, rather than "Dame".  

And that's all she wrote.