One gives you more of a stretch (full range of motion), but the other allows more weight (but not as much stabilizers)
The full ROM for the dumbbell bench isn’t necessarily an advantage — it’s possible to go too far down and get injured. It does allow you to have your shoulder in a safer position however because of how you can face your palms. The barbell bench press is the gold standard for upper-body strength these days, so it can’t be ignored. It’s the upper body lift that allows you to lift as much weight as possible through its full ROM. If I had to only pick one, I’d pick the barbell. You can also pick finer grained weight on it, meaning you can go from 245 to 250 to 255, but with the dumbbell you usually have to go 95 to 100 to 105, which is 5 more per hand. You can buy platemates to remedy this though. I do both though, and tend to focus on one for a few months and then switch.
