Well worth it. If they were $100-$120 they would be perfect. Would also prefer to have dual swivels instead of 2 fixed and 2 swivels (deducted 1 star for no option on this).That said, they lift my 650 pound (empty) workbench without issue. There were no measurement instructions I was able to locate. I found that if the top of the mount plate was 5-3/8 inches from the floor then the lift was near effortless.