The upside is that the SWU's appear to be very usable.

The downside (for me) is that you would only earn 4 for 160,000 EQM. My experience with AA's version is that while they pull from a more restricted inventory, they are still very usable -- usable enough that getting an additional 4 each year is worth it.

I also just noticed something very important about these SWUs. Once they are applied to a ticket, if you have to change or cancel that trip, you will lose the upgrade.

Steve