I hope you're talking about OFP:DR and not the original OFP.
I was about to say the same thing. OFP:DR I can understand. The graphics did suck and the game feels really bland and half assed. There are some good moments though, but few and far between.
The original OFP was great and I still play it.
I went and played a little Arma 2 recently and realized why I have been avoiding it. I only play single player BTW. The AI sucks so damn bad it's a joke. The graphics performance is laughable and the lack of physics makes for some bizarre situations. The controls have improved a lot but still are way too sluggish. It feels like your character is handicapped or something. The driving physics is so crappy I just shake my head. It's almost impossible to drive anything if you expect the vehicle handling to be..you know, realistic and what you'd expect from a vehicle.
I really wish this game engine was open source so I could fix these annoying ass issues myself.