Thanks to my friend Satsuki I got the SDCC Fortmax and it arrived today. I immediately opened it and compared it to my retail TRU Fort Max. I shall free you brother from your bonds of captivity! There are a lot more stickers that are not included in the retail version of Fort Max. You can see some of them and the subtle different paint apps.
I thought the space on the front of the tower looked odd. SDCC fills with with an Autobot decal. Old vs new master swords
Also there is a hidden easter egg with SDCC Cerebros. Press the button down for 5 seconds and it plays a guitar riff of the G1 theme. https://www.youtube.com/watch?v=YRiE7CU84nM&feature=youtu.be
It's a shame that the larger figure just doesn't do it for me. The cerebros head is such a great figure. The autobot theme is hilarious.