I just finished it.
I expect three things from an expansion to a game:
1. New levels
2. New monsters
3. New weapons.
This had a few new levels, mostly built with stuff we have seen before in HL2, and I think ONE new monster that wasn't terribly original.. and NO new weapons? And NO vehicles? Considering how prominent vehicles were in HL2 I expected at least one decent vehicle romp.
And why we still dont get that sniper rifle with the blue laser sight that combines AND Alyx uses is entirely beyond me. The crossbow is cool, but it fires too slow to pick off moving targets. (unless you can predict their movement)
Also there is the fact that it seemed to be about half as long as Sin Episodes: Emergence, or is that just me?
It didn't do a hell of a lot for the story either, we learn how Gordan and Alyx survived the tower, and we learn that the tower is sending a message somewhere, and then it blows up...?
Seriously when it ended I thought I was like HALFWAY through it. And I played it on HARD difficulty, and didn't think it was hard at all.
And I got really tired of having Alyx running her mouth and being stupid the whole time. What happened to the solo Gordan kicking ass without any help? The ocassional NPC is cool, like in HL2. The NPC that is ALWAYS THERE is annoying.
And Alyx has some seriously shitty A.I. I lost count of the number of times she walked right on top of a grenade, backed onto a grenade, or did something equally dumb.
And the Combines take waaaaaay too much damage to go down on hard difficulty. It can take absurd amounts of ammo to down one, unless you hit them in the head every time. And even hitting them in the head isn't a guaranteed one shot kill... I guess they have some badass armor and are completely immune to the kinetic energy knockdown force of a bullet or shotgun shells...
So basically this post is a lot of bitching, but I paid my 17.95, and I expected more. I won't be buying Episode 2 unless it is A) longer and better or B) cheaper.
I give it 3/5 or 65% (just because I like HL2 so much and it was briefly fun...)
Pros: Cool special effects in the tower and other places. Some cool scenarios and new areas. Good action and lots of attention to detail.
Cons: Too short, no new weapons, only one new monster, feels like a retread of old HL2 areas, few or no new textures, too much NPC presence, too much NPC babbling in general. No vehicle action, Alyx is overused and gets annoying, Alyx has bad A.I. , Combines take ridiculous amounts of damage before going down on Hard.
I really liked Sin Episodes better, and I don't think anyone can argue that the HL2 A.I. is way better or anything... at least Sin Episodes was a LOT longer, and more satisfying in general (to me).