Have had a good experience working with Altisource.  One problem for me that cause late payments is that I was not sending an invoice with the orders and would send an invoice for several orders at a later date.  This caused a delay, but after discussing with Altisouce Reps I understood their process; which relied on the invoice accompanying the order which included their order control number.   Other than that, which was really my fault, I have not had any problems.   I have not audited my books for last year, but it seems that they are paying everything is a timely manner.   I think they have a good system.