48k miles vs. $420. Not a great redemption rate, but if you don't fly UA much, then it might be worth it because those miles are basically stranded and you're not pursuing status or more miles it seems, which would make cash purchase more important.

Really hard to say from afar - that $420 might by the family some nice xmas gifts that you wouldnt have under the tree otherwise. Or maybe it's what you'd drop on a nice meal with spouse. Everyone has different values.