Do you have status that will get you extra bonus points? Even without status, it seems like the extra 15-20k miles are worth about the $175 in cash you would spend, so you might as well go with your AC trip.

Bottom line is if you get those miles in another program (Skyteam in this case) which you don't plan to fly with again later on, the miles are sort of pointless, but if you get them in your own program and use them wisely, there value is at or greater than $175.