Eyepiece Extenders

Eyepiece extenders have been a bit of an unknown area in the dSLR circles. Myself and a number of photographers I know prefer to use them to keep our faces off our LCD screens, and helps me judge framing and composition more easily. Two styles are available - the EP-EX15 and the EP-EX15 II. Canon list the EP-EX15 II as the suitable partner to the 40D, but as I found out when I got it, the EP-EX15 is the correct extender for it. For info, the optical characteristics of both extenders looked identical to my eye.