I used the munter last year and hated how much it twisted the rope. I use twin 8.0mm ropes, 9.5 canyontech and 10.1 static. Id like a device that can handle two ropes or one. My primary concern is NOT twisting the rope, if there is a device that can be configured specifically for that. I was looking at the Sterling ATS and petzl pirahna... anyone use these?