+1 IMOD is 9.4 oz on my digital postal scale, in comparison my EMOD is 14 oz.
I just got my FDE IMOD about three weeks ago to replace my 5 year old Modstock, the feature that I like about it is the angled and thread pattern of the buttpad similar to the EMOD.
The front of the old Modstock had a small vertical lip at the front end but the new IMOD is now smooth, and the lock paddle had been improved with better non-slip texture.
My minor problem with my old Modstock was the slip on rubber buttpad that if I don't tie down most of the time slips out or even just falls down to the ground, no more of that with my new IMOD.
I'm using my IMOD on my M4gery 16" with KAC M4 RAS rails, Surefire M951C light, and Aimpoint M2 with LaRue cantilever QD mount, I like the balance so far.