I haven't tried it out yet for sizing
But that's precisely why I built it. It was about $70 in parts since I went with the proximity sensor.
I was getting tired of placing every bullet in the sizer. But, the Lee APP for brass prep is phenomenal. My arm gets tired from how fast I can go. The bullet sizing should be the same. I put it on a piece of pipe on the side of the bench since I think I will need to lower it. Having that many bullets pushing down on the shuttle might be a problem.
I also almost have the case sorter done so I don't have to physically sort my 9mm anymore. That's been a lot more involved...a ton more electronics. The guy has done a phenomenal job on instructions and support:
View: https://www.youtube.com/watch?v=lhxDmvg5AVQ&list=PL6ub9IFZuQ5FrVuH2LGPoBVt1JWzbpzYu