I have Lee, RCBS and Hornady dies. They all work well. Most of my dies are Lee.
I have found that they work better in progressive presses than the RCBS dies. Since the price is half or less of other manufactures I have two die sets of the same calibre for different uses. I have one set to use on my single stage press when working up loads and another for my progressive press.
I donot like their lock rings, the adjustment can slip when you screw them into the press. I have changed all of mine to Hornady lock rings. They screw tight and have wrench flats if you get one too tight on the press.
I use a lee melter for my casting and it works fine. If you are doing a bunch of bullets you may need to add metal as you go but they work.
I have not used any of their presses so I do not know about them. They have a new press out that looks good and a friend has a Challenger press that he uses.