phreak, you really need to have a closer look at SPT. it's an absolute game changer! i know if I had a big purchase item I would absolutely use split it. imagine being able to hold those amounts owing on your offset mortgages for longer! imagine having months to pay off a product. and not adding another line of credit.
as a merchant: increase in amount spent, less Cart abandoning. and only changer 1.5<2%.
5% you say. I would say retailers are lucky to pull 5<10% margins.
as a consumer you would have to be stupid to use APT as a product. forget interest rates. fees very often MASSIVELY outweigh interest.