Don't take the Australian prices as representative. We get fairly shafted on pricing. Also they are AUD so take 20% for a straight USD conversion.

Machine #5 is the US i7 (you need to scroll right to get to machine 5 of 5). Quite a different group of configurations in the US. Intel Wifi on all, 128GB SSD on most etc. So top of the line is $1599 for you
http://www.dell.com/us/p/xps-13-9343-laptop/pd

There doesn't seem to be the a huge gain with the i7 CPU to be honest there.

As for the docks not working in the BIOS, yeah my "hub dock" is the same. It seems many USB3 ports don't work in the BIOS and likely many hubs don't either. If I have a USB keyboard plugged straight in it still works (even though the keyboard itself has a hub inside it behind which the actual keyboard lives). Should absolutely work by login time though.