Responsible design requires documented information provided by the manufacturer for the specific device. At least two other leading manufacturers (ON semi, and NXP) do not specify Iout for greater than 0.5v output drop with 10v supply. Characteristic Vo vs. Io beyond that point is undefined. Monolithicity is not a design parameter, and is not a measure of how well transistors within a specific device are matched. How well the transistors are matched depends on several factors, such as tolerances used in the artwork, variability allowed in test and manufactering, and control of microscopic variances in the wafer. Blah, blah, blah.