While it be on TV I have seen many elk get shot with one and they do not go very far, but as with anything you must make a good shot. I think the thing with mechanical broadheads on elk you just do not want to hit a heavy bone(ie shoulder), but I think if you were to hit a rib you would still be fine. I have used the Rages but not on an elk, I used the three blade on an antelope and it was totoally devastating, so I think with a good hit it should work just fine. I would just make sure your o rings are good so it does not depoly to early.
Here is a very handy and effective device I use to dispense corn with - but it could also be used to dispense any other seed or deer feed.
I had an old feeder that had a failed motor... I made a set of brackets to attach the feeder to the rear of the 4 wheeler - the lower one encircles the feeder and has a forward section with holes drilled in the outer ends of the bracket... these holes align with two 5/16" bolts that drilled into the rack of the 4 wheeler.
The upper bracket is an "L" shaped...