1.4 ii and 1.4iii extender

[Pick]

Is there much difference between the Mii and Miii 1.4 extenders.I am going to be using it on my 300mm 2.8 for football.is the price difference worth it

 

[bigrob]

Not unless you have or plan to have a version II of the 300.

http://www.the-digital-picture.com/Reviews/Canon-Extender-EF-1.4x-III-Review.aspx