Nice, one of my favorite thing about shooters is co-op. I'm really into that... I had a blast with Resistance's co-op. How long is RE5 on it's hardest setting?

Tough choice, but if just one, then Kz2. It is easily one of the best games ever.

 On its hardest setting?

Depends on what weapons you have and if they are fully upgraded/unlimited ammo. ME + my friend beat it on Pro in about 7 1/2 hours... this was with unlimited magnum ammo, the fact is... one hit from a majini is enough to take off your full life, so it makes it really hard to do if you dont have a co-op partner.

RE5 took me about 9 hours to beat KZ2 took me about 12 hours, but killzone has sweet online play

I should have probably just asks Naznatipz if this is the normal VGchartz opinion. One of the best games ever? Easily? lol

@Carl: 7 1/2 hours? So the game really is only 8 hours long? I liked RE5's gameplay a lot, but I need more than that. this is a tough choice.

@riot
SP
is like
11 hours(KZ2) Vs 8 hours(RE5) if you don't rush

Believe me , Valkyria Chronicles is one game that you should be ashamed for missing out, its very very very good.

Edit : Rent it atleast , before buying it.

@ Riot.
The first time through should take you about 9-10 hours. You'll also probably want to go through again to find the Emblems/Treasures that you missed the first time around.
If you played through on Pro difficulty without the infinate ammo, im guessing the game would last at least 12 hours, there just aint enough ammo lying around and youd have to keep restarting from a certain point or loading your last checkpoint.

That right there should solidify your choice. You know you will enjoy it, and yes it may be a bit on the short side but honestly which games outside of RPG/JRPG are not these days?

You also said co-op was a plus for you and RE5 co-op coupled with the fact that you enjoy it's gameplay should give you all the information you need in terms of making your choice.

I don`t like you, so I recommend RE 5. Took me 12 hours on my first playthough on veteran (4 hours at least were retries, the game was not designed to be played on veteran from the start). Should take you 6-8 hours on normal.