It's already been said dozens of times, but this is a mediocre attempt at copying Creed Millesime Imperial.
It doesn't smell bad by any means. As a matter of fact, it's a nice smelling fragrance. Which makes sense because I love Creed MI. But when compared with MI side by side, it smells quite synthetic. If you already own or plan on owning MI, then I find absolutely no reason to purchase or wear Unforgivable.
Sillage is poor and longevity is abysmal. When applied very liberally, I don't even get 1 hour on my skin.
I have heard from multiple sources that the Multi-Platinum version was a much better fragrance, but it has been discontinued for years.