I own RCBS and Hornady. I prefer the Hornady dies. I also own a few specific dies, Lyman Mdie, Lee FCD, Lee decapper, Mighty Armory decapper
Hornady
Sizing dies seem to be on the small side, so Ive never had issues with sizing enough
Seating dies are great, the guide sleeve makes life easier. I dont use the micrometer addon.
Expanders for pistol are terrible and were replaced with Mdie
I dont taper crimp, so I use a FCD
I think dollar for dollar, Hornady dies are hard to beat.
As far as vs other dies?
I have a friend that loves his Mighty Armory 223 sizing die, to the point he shelved his Redding.
Redding seater dies have the sleeve just like a Hornady, but Im unconvinced that they are worth 3 times the price. Maybe you might see a little better run out. There are a ton of arguments to be made either way.
Ive seen guys champion Dillon carbide 223 dies because they load 5000 rounds a year with them. I had a good laugh.
Ive seen guys have issues with Lee 300 BO dies when forming brass, and they had to switch to a "better" quality brand to get it to work.
So many stories like this. So my advice is simple. Buy whatever you want, Ill buy whatever I want. We will all be happier