I have both the Lee Autoprime and the RCBS tool. I like the Lee better. The Lee does not work on my 338 RUM. The cases on the RUM is too fat to fit in the Lee tool.

I like the feel of the Lee better, it seems like I can feel the pressure better, and I am more confident the primers are all being set the same depth. The Lee does tire my hand more than the RCBS. The Lee is less Expensive. The RCBS has several pieces to the kit, the only pieces to the Lee are the shell holders, extra pieces are just something else to get lost or forgotten. Also, the primers do not bridge as much in the Lee as they do in my RCBS. They do still bridge once in a while, but not nearly as often.

When I first started using the RCBS, the comfortable way to prime had the primers pointed directly at my face, I had to make some changes so the tool was not directed toward me. You may have a different natural grasp on the tool, the only point here is there is no replacement for putting each in your hand to see which is most comfortable.

I use the Lee for everything except the RUM.