1. what is your booking class?
2. DONT take the 3200 premium cabin upsell as this is just the fare difference between coach and the cheapest business class seat.
3. if you do miles and co pay you will only be charged if it clears fyi

I have flown this route probably 10 times. of the 20 legs I have missed it twice. Actually the only two SWU's that I have failed to clear in my life have been this route. Although I'm still 90%. Thus the miles/copay should be good, although what date are you traveling? We can look up the flight loads and give you a better idea.