Thinking about doing a few redemptions in China from Chongqing to maybe Chengdu, then Hong Kong and then Shanghai before coming back to Chongqing.

Does anyone have any input on the difference between Y and J redemption on DragonAir? Is it worth forking out 2x avios for biz class?

Also I am open for other smart RFS routes while I am down there as we will have about 7-10 days in total.