Don't you agree that a 3.5M house is a luxury Item and people should pay cash for that?
Yes; I personally would never buy anything above conforming limit unless I bring enough cash to reduce the loan to about $500K or so. Now, there may be some special circumstances like need to shelter large income from taxation (i.e. tax writeoffs) or need for cash for working capital if you are in a business (using lower rate mortgage as a business loan). But if raptorduck is certain of his cashflow, he may be smart in borrowing at low rate and buying an attractively priced asset that is definitely going to hold its value and payback with cheap $ later. I would consider RSF/La Jolla/Beaverly Hills etc., to be in that category. You are basically shorting US $ in the long run (30 years), which is a very good bet to take knowing what we know now about the coming entitlement tsunami and how it is practically going to destroy $ as we know it.