LAX-PEK is problematic, SFO-PEK is easier to get J or F seats - it's a 747-400 so the product is different than the 777's out of LAX but for 10K miles diff each way F on the 747-400 is actually a better experience than the 777's in Biz.

I'm on SFO-PEK a week from now in F flying LAX-SFO to get on the flight. Will try to do a trip report.

Before anyone asks I do fly Air China Long Haul to/from PEK from US and elsewhere in Asia every now and then, sure it's not SQ or NH but in F or J it's more consistant than UA where I've had VASTLY different experiences with great pm-UA crews and pm-CO crews and TERRIBLE experiences with both crews.

Try SFO-PEK even if you have to pay for a cheap Southwest ticket to go from LAX-SFO ; just plan to be in SFO 4 hours or more before the connecting SFO-PEK flight in case of weather into SFO.