Also consider that for things like cyber work, the frontier models give you nerfed results and poor performance. Whereas the open weight isn't nerfed, and I routinely get 200t/s with my subscription. Finally, DS4.1 Flash is natively multimodal, while Haiku isn't.
They're all perfectly fine models, you should use any one of them you want. But DS4.1 Flash can do more for less. (That said: GLM-5.3-Flash is even better and cheaper...)