The best review of the kits is at this site.
http://www.mheaust.com.au/IDF/Reviews/M51/background.htm
It's written by Tom Gannon, who probably knows more about IDF Shermans than anyone else and has written an excellent book about IDF Shermans.
Personally, I have not seen the Academy kit, but think that the DML kit with the Accurate Armor update set makes a great looking kit.