For me my 12K 2 post lift is one of my favorite things. I use it for a lot of different things. a couple of lifting straps are really handy. I unloaded my lathe with it and even pick up the mower to sharpen the blades. I wouldn't get too worried about the concrete. If you have up to code floors with the proper reinforcing in it you will be fine. Your concrete should be at least 3500 PSI. If you do the math there is more PSI on your tires than the lift has. Mine has 16" X 16" pads. I would be more concerned with the anchoring. We use large tapcon bolts for our large equipment in the factories I build. I'm a commercial general contractor.
