3 vs 4 die
Not sure what you are loading 45 ACP for, bullseye, steel matches or just plinking, but the three die set will handle probably 99% of your reloading needs, lead, plated, fmj, hp, swc. Stick with published or trusted reload data and you'll be just fine. You'll get varied, but generally honest advice on this forum, and its free. Those of us who remember the 60's remember the old saying, "Free Sex", "You Get What You Pay For".
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