I'm sorry but you must check this out; www.realitymod.com.
It's basically a mod for Battlefield 2, check it out, and the videos. It's much more complicated, and realistic. It looks great, it takes about 3 hours to download on an good connection, (not sure how fast.). I'm getting it.
Theres new weapons, a Vehicle damaged system, for example, if a tank drives over a mine, and it's tracks are damaged, it becomes immobolized, and can't move until repaired. Also, there are more kits, which you can check out in the FAQs and guides. You also need to be a seperate kit, to drive/fly important vehicles. Such as Pilot, Driver and Crewman.
Also, there's blood, wehey!
If you scroll down some on the Battlefield 2 forums, you'll see a thread where Project Reality has already been discussed.
Cheers.
Genaxx