Playing the PC version right now.
First thing I will say is about the DRM that comes with the hard copy of the game (not Steam). It is apparently nasty enough that by default, windows Vista will not allow the game to run (Data Execution Prevention prevents the game from even running).
Make of that what you will. But it is probably not a good sign when even the operating system you are using does not want to execute the DRM.
As for the game.
It is fun, but has a fair few problems.
Firstly, the game is disgustingly easy. I am using Mordecai and going down the gunslinger skill path (which specializes mainly in pistols). Mordecai is probably the most fragile of all the 4 characters, but I am rarely taking any damage from anything, and rarely come close to being killed.
Also, I can use a sniper rifle to basically 1 hit kill anything (including bosses), from a very long distance. I have absolutely no specialization in sniper rifles either.
The UI in the game is horrible. It looks nice and all, but the controls for it are stupid.
You have to use the mouse, arrow keys, enter and escape. It is really annoying that you have to keep constantly changing the controls you're using just to navigate a menu.
As for the game it's self. Controls are fine, but you will probably want to change them before you start (they are spread out over the keyboard too much initially).
The game is fun, but lacks variety. The quests are all kill stuff, or collect items. The enemies all look or act similar with very few actually being different.
Gun in the game also do not have a lot of variety. I suspect the "17 million" guns or whatever they claimed the game had accounts for even the smallest of differences. I was at one point holding 4 of the exact same gun, or nearly the exact same. They has the same name, same stats, but the only differences were minor differences to their appearance. One has a little iron sight on the end of it's barrel, another had a slightly bulkier looking grip and so on.
Also, the game tries too hard to be funny, and fails at it.
Whenever you kill someone with a critical hit, or with your special ability (for Mordecai at least) your character says some crappy one liner.
Some of the weapons are obviously spoofs on internet memes as well. I have found a "weaksauce" gun (literally, it's name was something like "Weaksauce Repeater"), another was a "Rage" gun, and there is probably a lot more in the game like this too.
There is a lot of other, unfunny stuff in the game too :[
The game is also somewhat buggy. I have ran into three or so at the moment.
One was an issue with clipping and me being able to see/move through a part of a building.
Another was with enemies acting like retards. (I was shooting one, and none of them would do anything, other than spout out their one liners)
The other was some sort of issue with me handing in the same quests like three times.
Nothing major at the moment. But I did not particularly do anything difficult to run into them.
All in all. It is a decent and fun game. But I doubt is has a lot of replayability due to it's very easy difficulty and lack of variety with pretty much everything.