After I finished the campaign on normal (just to get back into the swing of halo) in about 3 hours I decided to try firefight. My girlfriend (Kimsu87) wanted to play as well and I was a little skeptical after watching her play CoD4 and other shooters. I knew there was no way just us two would be able to get the cheeve for 200,000 points.
But to my surprise we well surpassed the 200k point and after 136 minutes we just decided to call it quits and let the hammers own us.
I had something like 188k in point and my girlfriend had about 75k, but I was very proud. We're planning on doing the rest of the maps some other time if anyone else wants in on the cheeves. Let me know.