Ok THANK GOD you did'nt start the armor yet. I found this thread and I said WOAH lots of incorrect info here. Firstly, the SPI armor is supposed to be more flexible and easy to move in than any of the Marks. It also has an inherent active camo ability. Also, the rendering the guy did took LOTS of creative license because the SPI armor is supposed to have a more rounded organic shape. If you want direct quotes from the Ghosts of Onyx you'll have to wait because my friend borrwed mine. Oh, and the SPI is actually newer than the MARKS as it was developed for the Spartan IIIs. While its newer, its simpler, to cut down on cost. I recommend you read the Ghosts of Onyx, and make your own sketches on top of his as his armor doesn't capture what SPI is all about. BTW I'm a Halo universe expert so if you need any book info, I'm da man.