I have the 24L, 24-105, TS-E 24 II, TS-E 17. My TS-E 24 II is hands-down the sharpest of all my lenses, including the 70-200 f/2.8L II. It is super sharp without the tilt-shift, but is corner-to-corner sharp when the tilt is used properly, even at f/3.5. Although some use tables, LiveView is the easiest way to get that sharpness. My recommendation is to buy a clean used copy. They go for $1,750 USD or so.