I'm mostly a commuter so I'm always on the lookup for casual type cycling clothes. Does anyone have experience with these below-the knee knickers style shorts:

My big question is- does it snatch on the knee when you are pedaling? I have a pair of MTB shorts that are on the long side and the knee wants to pull on the top part with every stroke (until I learn to roll up the shorts) . Does this happen with these knickers?