Don't waste your money on this, it's the worst HL2 mod I've ever played.
Here's my review of the newly released Prospekt.
For those who don't know what Prospekt is, it's a fan made suite of Half-Life Opposing Force whose author decided to send to Valve along with his C.V. to get hired. The author wasn't accepted but Gabe liked the mod so Valve ended up helping him and ended up being a paid HL2 mod after buying the licenses. Now on to the review.
My first disappointment is going to be the level design. I expected the maps to reach the same quality HL2 had or even HL2:EP2. I think I good portion of the maps could be recreated within GoldSource with "env_model" and sometimes there are no "clue" or "hint" to guide the player. For example, you arrive at an area where you have to press a button, then you have have an infinite antlion spawning behind your ass and you end up wasting 3/4 of your ammo before running everywhere and finding out you have to play Super Mario Bros to reach a ventilation shaft.
Second disappointment is the gameplay, you just run, shoot a lot of Combines, solve puzzles, listen to Shephard's flashbacks, repeat. There are very few variety in enemies, 98% of Combine, 2% of Headcrab, zombies, antlions. I was playing in Hard but I had to go down to Easy because the mod's author had the "great" idea of giving twice health to NPCs and not a little bonus for yourself. Seriously, emptying a clip of pistol in a Combine's head don't kill him on Hard. And speaking of weapons, the only arsenal you have is the standard HL2 weaponry without some weapons like the crossbow and RPG. I've finished the game (almost by speed-running) in almost 2 hours so I expect professional speed-runners finishing it in 1 hour and 30 minutes.
Third disappointment is the story, you are told at the beginning to help Freeman stuck in Nova Prospekt and you just hear some Shephard's flashbacks of his story before he get involved in the Black Mesa incident, that's all. Where is the powerful narrative element that we all loved in Half-Life ? There is none. There isn't a single friendly NPC.
Fourth disappointment concern technical aspects, I've already tried to validate the game cache and all but it seems that when you run the game on Low settings, you get the magnificent black/purple texture of Source, and let's not forgot how my eyes just bleed when looking at the game files.
I tried to find positive things to note but I didn't found any. Prospekt is just a paid map pack and a huge disappointment for those who liked Adrian Shephard and wanted to have a good time with him.