Yeah, IMO any FL sizing die at station 1 is better than a universal. It will iron out the neck with the carbide ball and set you neck tension. Then the sizer/trimmer as I said before just mimics the initial sizing without setting the shoulder back any further. Just set the trim length.
There have been guys that use a universal to decap, them size/trim with the RT1200, followed by collet/bushing neck sizing to set the neck tension with more consistency. I personally have never seen the need to add the extra step.
I believe using my method... you are already sized so when you run it through the trimmer there is no stress on the brass as you are trimming, so the trim lengths are more consistent.
Glock 3rd Gen G19/G34, 4th Gen G17 FDE, G26,
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