AMEX Reward to Qantas Frequent Flyer Points transfer bonus offer - Should I transfer my points?

Hi There

I have 390,000 Amex reward points earned via a Amex platinum card. I only have Qantas FF membership. I prefer holiday travel in Business Class. Should I take current Qantas offer with 25% bonus or hold these rewards and use with another airline. I intend to travel to Europe in 2018


Please see recent similar question here.