I attended a free-motion class at the LQS and was instantly sold on Machingers ($8) from listening to the women's experiences with them. I used them for the first time yesterday. What a difference! I totally agree with what everyone else has said about them. They definitely increase friction, making it easier to control/move the quilt sandwich, but what I really noticed is how they reduce fatigue not only on my fingers, but also my wrists, elbow and shoulders. Oh my! That was a shocker!
I wore them from 7pm until 3am! I was so intensely focused on quilting that I didn't realize my sewing room got up to 92 degrees. I use CFL bulbs too, but something heated up my room. My point is that despite the absurdly elevated room temperature, my hands did NOT sweat or feel hot. Machingers are ultra thin, very comfy and appear to "breathe". I didn't feel like I was wearing gloves on my hands and yes, I could thread the machine! Amazing.
I might try garden gloves due to their low price, but I'm hooked on and definitely recommend Machingers.