I think it's a huge difference and I would never buy another mtn bike without thru axles. The reason I like them is they lock the wheel in place MUCH more accurately and perfectly than the thin qr axle so you can expect your wheel to be in perfect alignment all the time. With a qr axle, properly tightned and all, I can stand on one pedal and shift my weight and often get a brake pad to touch. I like my brakes setup close and with disc brakes the thru axles allow more perfect alignment, repeatable each time the wheel is removed. It's simply superior. Higher end bikes have them for a reason. They aren't such a big deal with rim brakes but for disc brakes they are the bomb and like I said, I'll never buy another mt bike without them.