If you'll fly 80K next year, one tangible benefit is 37,500 more bonus miles: the difference between 25 percent bonus for Gold and 100 percent for PLT for the 50K until you'd be PLT anyhow. How much are those worth to you?
If you're not an AC member, figure $50 per overseas trip as the rough value of AC access. If you are, or won't fly overseas, this doesn't matter.
Other things, like shorter waits on the phone and an earlier shot at upgrades, are gravy. If it's close, let them push you over.
And I agree that there ought to be cheaper ways to do it, especially if you can drive from Palm Beach to FLL or MIA. One good idea has already been posted. At ElmhurstNick's fare, it should be a no-brainer.