My employer covers an economy ticket, but I used 20k miles and no extra cash to upgrade to a Polaris seat. The pricing on this route also earned me about 10.5k miles back due to how expensive it is. In the end, I effectively spent nothing and only 9.5k miles for a Polaris seat on an 8-hour flight, which feels like a great deal overall.
For context, the route is Guam to Honolulu. United essentially has a monopoly on this route, so even though similar 8-hour flights elsewhere can be much cheaper, this one usually starts around $1700.
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