I tend to agree with the factory blades. They definitely leave a good few lines as it passes through both sides actually.
As Preppie suggested, I cleaned them off with some of those alcohol wipe packets every time I washed the car.
For the summer it wasn't a huge issue but for winter they're definitely getting changed.
Longer blades won't do anything. Just get better quality.
Or we can jack these off of a Merc...

(although I'd worry about them getting plugged in the arm)
https://youtu.be/07AZHkkLR0k