What's "Best"? Well, that's somewhat like Ford vs. Chevy! They all work but the right answer depends a lot on what you will want your new Chronograph to do. If all you want, now or in the future, is velocities then the various Chronys offer the biggest bang for the least bucks.
I wanted more. Wanted things like a built-in printer, a good ballistics computer, a seperate display/computer to sit on the bench and outta the line of fire, and low replacement cost of the optical screens if need be. That led me to the PACT Pro and I have no reason now, after 12 years, to feel I made a mistake. Don't know what an Oehler, other than their fablous and expensive Ballistics Lab model, could do better for me. (Never shot a screen, but it's still an option each shooting session!)