I have the Hornady unit. It works, it works well. I would not load rifle rounds with anything other than Trail Boss without it. It is pretty dog gone quick as well once you figure out exactly where to get it to slow down to trickle the last bit. Mine was gifted to me by some one that knows I am way to cheap to by it for myself. Though if something happened to the one I have. I would buy another. Though I would probably get the Lyman.
I use a powder measure for my pistol loads. For loads that are less than 10 grains of most powders it is a bit on the slow side.
I will not load for .30 Carbine without it. For some reason loads do not cycle in my rifle unless they are on the butt crack of max load, and the spread from start to max is exactly 1 grain so care has to be taken. It takes less than half the time it would take me to use a powder measure, and trickler to weigh each round.
No matter how many times you do it and nothing happens it only takes something going wrong one time to kill you.