As long as you get flights w/ the proper fare codes, you can apply to AA and get status with them. Their redemption is better for long haul. Asia Miles is better for short haul, but as others mentioned, some of their really cheap fares don't accrue miles.

However, Silver on Marco Polo gives you access to the Cathay Lounges when flying them, so that's another consideration. Need 30K miles to qualify MPC.