Incredibly important question for the day: why do so many new vehicles use windshield wipers of two different lengths? Just replaced mine on the X with 24" and 18" wipers, but I don't understand the advantage of having them this way instead of two wipers of the same length. Works fine, I'm just not seeing the reason for this. Experts?

It's really just a geometry thing. Take a look at where they put the wiper pivots on new cars, and then consider how the blade lengths affect the cleaned area.

With offset blade lengths, manufacturers can put the wiper motors/pivot points where they make the most sense from an engineering standpoint.

i have 21's on mine right now....

they work for me ...... i like the windown to be clean .. should have got 22's .. but next time...