Damn, I tried to order the Mercier Kilo WT5 because the webpage said the 49cm size was in stock, but the order wouldn't go through and when I called bikesdirect they said they don't have anymore and took it off the site:
http://bikesdirect.com/products/mercier/kilott_wt5.htm

...and now that I spent all this time considering the virtues of the Kilo I don't want the other bike!

Where can I get a bike like the Oxford with double butted tubing or, perhaps, aluminum?