Used in a commercial gym recently with a full Matrix line. I typically do my leg extensions with a single leg to keep any imbalances at bay, so the stack was plenty heavy for that. The range of motion could have been a bit better, which was inhibited a bit by the edge of the pad which goes under your knees. You ideally want that as close as you can comfortably get to the crease of the back of your leg or else it gets pretty rough on the patella tendon
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Build Quality