I am looking to use miles from US and have a choice of UA vs. QF. Should go on QF or UA have not flown neither one. I know there is a difference of 15000 miles between the two. Are the extra miles worth it to give to go on QF. Second we are not set on the dates, so we are flexible to get the award seating when available. Please advise to the best time to grab two seats in business class. pbi-lax-syd. Thanks for the help and love this website.

SCA Gold DM, Silver DL, Gold HH