I need to make a legitimate flooring upgrade in the shop. Due to sore feet, knees, back, I've tried all sorts of boots and various floor mats around the shop which has helped a lot, but I need to jut bite the bullet and get the whole shop done. I'm assuming that going with a heavy duty rubber mat, interlocking, is the best choice but am wondering if others would agree. If so, what brands, thickness, etc do you recommend? If not, what other option should I be considering?