POPS, you will probably find the dealer would be happy to order one early and put the paperwork throgh on the 12th.
From what Ive heard the i6 does not wallow as the i5, having road manners more akin to German manufacturers (Bjorn Nyland). I also think the new i5 still uses HDA 1.5. Other than that, they are the same car with different coats on.