The hexes are more efficient since there is no corner to corner issues.
http://www.cartographersguild.com/at...map-final3.png
http://www.cartographersguild.com/at...upload-001.jpg
http://www.cartographersguild.com/at...upload-002.jpg
http://www.cartographersguild.com/at...ewmap-copy.jpg
http://www.cartographersguild.com/at...porjection.png
http://www.cartographersguild.com/at...ectangular.jpg
The hexes are more efficient since there is no corner to corner issues.