OK, Lets start with the obvious. Great concept, light, and versatile. I carry the Rush 12 insert in my Rush 72. I also have trained to remove it from my backpack and slip it under my T-shirt and trained to see the stability as opposed to hugging my backpack. It worked very well, there was some slipping as sits is loose, but overall stayed fairly stable while shooting.
Now for the fit. I travel around the country training and my Rush 72 backpack is my office and travels everywhere with me.
There was not an insert for the 5.11 Rush 72 backpack. I measured the pouch and I barley had 17 inches. The Rush 12 is 15 inches high. I thought the 17 inch insert would not squeak by, so I went ahead with the 15 inch Rush 12 insert.
Low and behold, I had more than enough room for the 17 inch insert. Width is the same and was fine.
So, anyone with a Rush 72, order the 17 inch insert.
Very pleased with my purchase, would not hesitate to recommend (and have) to others.
MADE IN THE USA ! ! !