It is still sitting at Bestbuy, I changed my mind and decided not to pick it up (Bestbuy will cancel the order automatically if I don't pick it up within 3 days) because Black Friday is coming, and then Christmas, so I thought I should wait. The little AVR-X1800H will hold me over until then. Also, I listed the 1800 on eBay but no bite yet, so again it is better for me to wait. It is tricky to buy AC4L that is in the USA, they wouldn't even sell to Canada before but it seems that now they do.
If I could wait till next spring, the replacement model should be out by then, or the AVR-X1800H will drop further. In the mean time I may just add another sub to see if I could fill in a couple of dips in the 60 to 100 Hz range, even with just the two subouts that are not discrete. Other than that, there isn't really any reason to replace the X1800H.