Lutron employees torsion springs in their battery operated roller shades too.  Not sure who holds the patent on this, but both companies are doing it.

Hembar alignment isn't that big of an issue if all the shades in the room are the same height, have the same fabric and have the same roller diameter (roller diameter is most important).  For QMotion, I think they only have one roller style so it's not that big of a deal to not have hembar alignment feature.

Lutron has tubes with different diameters that can be mixed in the same room, so in that situation, it's very important to have the intelligent hembar alignment feature so they move together.

I do Lutron because on my projects almost always have Lutron lighting control so the seamless integration just makes sense.  I believe Lutron also has more roller shade fabric choices and a much larger selection of shading solutions and custom offerings.

QMotion does honeycomb, roller and drapery.  Lutron does these plus curved drapery, Roman, Venetian, and their newer products like horizontal sheer, pleated shades and the vertical drapery (Kirbe).  I think another important thing Lutron offers that QMotion doesn't is all the top treatment options.

From what I've seen Qmotion has a nice product, but just doesn't compare to Lutron when it comes to control and custom options.