I think the front end is similar to the Insanity, its the back end that differs. I sold my 5' 9" Insanity so I can't do more comparisons. I do have my measurements for the Insanity, as I measure all my boards.how gey should I be for the goat if I love the insanity??
5' 9" (stock)x19..25x2.4 (30.5L) had tail width of 14.75" @12" up, and nose width of 14.1" @12" down. Tail lift was 1.6" and nose lift 4.75". You can see similarities with the GOAT - similar rocker. Insanity has a slightly narrower nose, and 1" narrower tail relative to the Goat. Note I use the center of the board of the GOAT owing to the asymmetry.
The wider tail of the GOAT allows it to work better in smaller waves than the Insanity.
For me, the Insanity is a good board, I want a shorter one because of its forward volume.