Actually, the 5XFAD mice seem to be the best model. 

Th

APPswe/PS1dE9 I worked with it and gave good results, otherwise you want to study the hyperphosphorylated tau, another model P301L

New mouse model reveals how Alzheimer's causes dementia 

Using a novel, newly developed mouse model that mimics the development of Alzheimer's disease in humans, Johns Hopkins researchers say they have been able to determine that a one-two punch of major biological "insults" must occur in the brain to cause the dementia that is the hallmark of the disease.