In regards to the SFO-SIN-SFO flights, I was fortuante that I had my own row each way (both flights were rather empty). I was able to snag a pillow from Polaris to sleep on, as one of the seats was not working correctly and they didn't allow anyone to sit in it. As someone else mentioned, I kept myself on LA time and slept my usual hours (1230AM-830AM), which helped prevent any jetlag. I landed in SIN, took a quick shower and ate, and got back on the plane while continuing to be on LA time. I didn't miss any work and never felt the effects of the time/date change.
I made the mistake of not upgrading my flight back when I landed in Singapore. I was initally offered to upgrade to Polaris for 30k miles and $600, which would have been a nice treat on the way home, but I didn't do it quick enough and when i got to the gate, it wasn't available anymore
I really wanted to do it for the pajamas.
Brian