The Elite Patao carbon cage has a funnel type upper lip (see pics), that should allow the angulation on bottle entry that you seek.
The Patao is used by professional teams, such as here on Landis' bike. It really holds bottles securely.
I got mine from this Hong Kong ebay supplier for $40 each (Patao's retail for $ 90).
http://cgi.ebay.com/New-Elite-Patao-...QQcmdZViewItem