Pitch Black... you HAVE seen this one right Posh?

Yes I think he has. He mentioned about it.

I have it, it's ok. I neeeeed something that can compare to Dog Soldiers and Aliens though. That's a hard find....

Predator? The Thing? Hidden? Dead Heat?

I liked Pitch Black more than Dog Soldiers (but barely, loved em' both) so what you're asking for is opinions. :)
Do you like humor to be a part of it? Tremors, Dead & Breakfast, and Slither are all great "survival" movies if so.

Horror Express may count as well...

Looks like the (?korean?) film "the host" could be worth a watch for you...

Not that it was really GOOD, but "mimic" had a similar feel.

Tremors I'd agree on...although the sequels just seemed to get more and more stupid (never saw the 4th)

Screamers?

If you wanna get stupid, maybe pirhana?

Tremors is great, I need to buy that soon. I like Pirahna, and most of the othe suggestions. Humor is fine, D&B is hysterical. Hmmm... It seems like i've seen most of them. Except:

What are Screamers, Hidden, and Dead Heat about?

Yeah, Despare's right, try Horror Express. You'll love it.

Before you ask, yes, it's a survival horror movie, yes, it has an awesome creature in it.

There's also "metal beast" , that wasn't great though...
I guess the first starship troopers had a slightly more frantic/comic version of the "feel" from aliens.

My fav. from the series.