@bbkenney -- It depends where you need to go. thepointsguy just posted on his blog about the 50% transfer bonus on Amex to BA or DL and gave several travel scenarios.

I'm actually thinking about SFO-SIN this November. The availability on CX is probably better than JL; there are two CX SFO-HKG flights per day and 8 HKG-SIN flights per day. A 100k BA miles RT in C is an excellent deal and the taxes are around $300 USD.