Which combo is better for Katarina QEW or EQW?

When I used her in ftp rotation, I used qew for normal harrass, and after they realized what I was doing and backed off when they got marked, I used my deceptive e range to eqw

why are you harassing with E and W? that's liable to get you killed.

depends, qew leaves less time to react, but eqw got more range

Nononono, range is not really what it's all about, Sure it has some more. But EQW is better since you Do E AA Q W AA in the same time as if you would do Q E W.