Are you the type who'd rather spray once in the morning and forget about it, or don't mind touching up?
The concentration stuff is legit, but here's what gets glossed over: eau de parfum isn't just stronger, it's *different*. Higher concentration means the fragrance oils don't get diluted as much by alcohol, so the actual scent profile develops differently on your skin. It can smell noticeably richer or more complex, not just "more intense." That said, you're not always paying double for double the oil - some of that price bump is definitely the brand flexing their prestige tier.
Where it matters most is if you're buying something you *love*. If you're lukewarm on a scent, no concentration level will fix that. But if you've found a fragrance that works for you, the eau de parfum version might genuinely hit different and last all day without reapplication. The problem is brands don't always release the same fragrance in both concentrations, so you can't always do a direct comparison. If you can sample both before committing, that's your best move - some people notice a huge difference in longevity and staying power, others find the eau de toilette perfectly serviceable depending on what they're doing that day.