For the first time ever, this offer prompted me to use points to fly in Y. I've booked MEL-SIN at 14,000 points + $130 one way. The cheapest return cash fare available on my dates was $770 (with SQ). So even if we assume the cost of the one way trip would have been half of that, this would represent a saving of $255 for 14,000, which is about 1.82c per point. That's acceptable value in my book - although it's certainly nowhere near what I have achieved on many occasions in the past, it's a trivial amount of points - e.g. I made 10,050 points for $16 last week with the IG offer!
In reality though, the value is better than that in my case, as I want to fly back with SQ in J on points, and buying a one way cash fare is prohibitively expensive. Additionally, by flying out with QF I get F lounge access in MEL, as opposed to the SQ J lounge, which is pretty ordinary. And I didn't want to fly return with QF as they only have a night flight on teh way back. So all in all this offer was worth it for me, but as always it depends on individual circumstances.