I have both a Rock Chucker and the Hornady Iron press.
I run loads for 4 different 300 Win mags and 2 338 Lapua Mags on the iron. I only size and seat on this press.
All other rifle calibers go to the rock chucker.
I actually like the Iron press, the way it feels when the handle is pulled, compared to the rock chucker. The Rock Chucker feels like it stopped short at the bottom of the stroke by comparison.
The Hornady Iron press linkages are starting to loosen up a bit. Enough that I'm thinking of getting some washer type spacers to tighten it back up.
Also, if your shell holders are knurled, they won't fit in the shell plate adapter that attaches them to the ram of the Iron press.