Fragrance lasting on skin varies from individual to individual.
Generally if you have oilier skin then fragrances will last longer, drier skin they tend to fade quicker.
It also depends on whether you're purchasing an EdP or EdT as EdP have more essential oils and last longer.
There are ways to make a fragrance last longer on you.
AHS and BdC are totally different fragrances so if you like AHS I would say purchase it.