Thank you all for the responses and warm welcomes! This would be corporate travel, so would book through corporate travel agency. Can book on either OS or UA stock (price is the same). Goal is to achieve status with UA (and in turn, *A status). If I book on UA stock, can I select OS seats in advance? Any "downsides" so to speak of booking on OS stock? I'm a general MP member, so mileage credit would be 5x the ~$4k ticket = 20k miles, versus the 8k miles traveled on OS stock. Plus the PQDs.... seems like UA's the winner? Again, would love to know about any "drawbacks" to booking premium OS class on UA stock. Cheers!