Thanks everyone. I don't like spending the $700 cash, and I realized that I could do points plus pay and still get the SC. However, I'd need 65,000 points plus $200. I just used 50,000 points to upgrade from PE to J on the DFW-SYD route. That was worth a lot more than $500! So if I'm going to do this, it will have to be with cash.
The problem is that I may be moving out of Australia later this year. If so, it would great to have Platinum because the soft landing to gold will save me plenty of money in baggage fees in the US. But $700?
What is the value of Platinum over Gold, other than a fancier lounge and the soft landing the following year?
You'll get the soft landing next year, and probably another year comped on top of that if my experience and that of many others this year is reliable.
In the US, requalification is easy in domestic first class, particularly just for Gold, which also gets you lounge access over there (as long as you have 4 QF flights).
I'd say it is worth it just for the extra year or 2. There are lots of small extras (more points, more award seats available, fancier lounges, quicker checkin, better upgrade chances, occasionally preferential on-board treatment, more likely to have a free seat next to you, more likely to get status matched elsewhere, etc.) that sweeten the deal too. I particularly value the First lounges if travelling much internationally.