Right after my kids were born my travel came to a screeching halt and my wife was all over me to fund their college savings accounts before making any "fun" purchases. I used a bunch of UA points to buy a Harman Kardon surround sound system. I'm guessing it was around 50k miles... I actually don't regret doing it as I have gotten hours of use and happiness from the system that I probably wouldn't otherwise have.

I wouldn't make that choice today now that my kids are older and we are traveling again. But I also have no regret for the choice I made 6 years ago.