Combined Arms will attempt to deliver land combat to DCS; intially the fidelity will be somewhere between arma2 and bf3 but you will be able to take fps style control of a tank or sam or command a group of them and take on the flyboys.
Once EDGE (the new dx11 terrain for dcs world) is relesed then there will be an opportunity for third party dev's to build high fidelity modules of land vehicles and sams.
Tanks probably won't be at the high fidelity of steal beasts but the sam is possible; a Hungarian built a good one a few years backhttp://www.rockpapershotgun.com/2009/12 ... simulator/
and if your thinking of building a sim pit make it modular as you might want to slide in those tank controls and take control of a tunguska.
Next year will be when this all starts to bloom, especially when EDGE and the nevada is released, but we will have a great start this year when combined arms becomes available.
and yes, these sims require a good amount of time especially reading time but some of the weapons system are similar which can save you time.
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