Back and forth flow is generally better.
The Koralias still produce a laminar flow, it's just more "wide patterned". I'd compare a Koralia to a box fan and a Maxi-jet to an air chuck on an air compressor. Similar "cfm" but much more pressure on the MJ.
I own both Koralia and MJ. Koralias are nice, but they sometimes stick "off" after a power outage and have to be tickled to get re-started.
When you put the MJ's on a timer, you can get some nice and natural looking sway going.