OK, so I'd like all of your opinions on my options. I can get all the way from BOS to PVG on SQ for 80K DL miles in Y (BOS-JFK-SIN-PVG), and then transport myself from PVG to PEK somehow. I've found flights on Air China for ~$350, which seems somewhat pricey.

Alternatively, I've found a ~$1,250 fare on Air Canada (BOS-YYZ-PEK). The travel time is significantly less, and the fare (considering its olympics) is pretty inexpensive. However, I've heard horror stories about AC, and especially considering my other option is SQ.

Third option - pay for SQ or CX flights for around $2K, directly to PEK.

What would you all do? How much better is SQ than AC? Should I save the miles for some other time?