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Looks better. To my understanding the M vein goas all along the wing, so the combination of the last two images would be an even better way to show it.

Now you can see that the M vein does have a bend! Tachinidae, Rhinophoidae, Sarcophagidae and Calliphoridae have this bend. Muscidae may have a slight bend, but typically it is more like a curve. Anthomyiidae does not have a bend, the M vein goes straiht or at most slightly curved.

Of course the difference between a curve and a bend is philosophical.