There are some lenders out there who use non-FICO scores, but the vast majority of lenders use FICO scores as well as internal scoring models. In fact, some lenders also use a BK scoring model to predict your likelihood of filing for BK.
I am curious as to why some lenders, despite the overwhelming majority, use non-FICO scores. They might be inexpensive. But if they are not reliable, they are obviously not worth it.