Should I buy Arma 2 OA?

I never play the game till last night when I played Operation arrow head demo. I reallly like it but find it dramticallly diffrent from anything I playedand very difficult.Im getting board of BFBC2 andI do like coop games. Is Arma worth it? I herd arrowhead is the best version. Can I start there? ALso will my PC handle this game well? Do people play online? ect.....

Get arma 2 before OA thats my advice

If you do decide fork out the extra $10 and get combined operations. Well worth it. A lot of servers require ArmA 2 nilla and ACE2 mod which is ArmA 2 only atm I think..

I say get it! Just be patient and take your time, you will be rewarded with a fantastic realistic shooter!