In my tests they do quite similarly, but 3.8 flash next is considerably (2x) more efficient and faster to respond.

Both 27b and flash next are more stable on "low" reasoning, only for generative /creative tasks, xhigh could be better, but both suffer from way too much reasoning at xhigh. And neither really support high, so low is the best reasoning effort.

[0]: https://aibenchy.com/compare/qwen-qwen3-8-27b-low/qwen-qwen3...