I fly the MIA-LAX on the 777 all the time. The plane is very comfortable which makes a big difference on this 5 hr flight.

The IFE (in-flight entertainment) is good too, but I bring my own Bose earphones and my laptop to view the DVDs of my choice. I listen to the audio channels once in a while and I find the variety of music to be very good. The only thing is that using the regular earphones they give (sell) you makes it a miserable listening experience, so bring or buy a Bose for yourself. You won't regret the purchase if you fly a lot.

The service/food is a mixed bag. Sometimes you get excellent service and sometimes you don't. These inconsistencies are widely discussed here on FT. But YOU'll have to draw your own conclusions about attitude, service, being called Mr. or Ms. appropriately, hot towel, warm nuts, metal tongs, etc...

My opinion about upgrading: go coach and come back in business or vice-versa. Save some miles for your next adventure.