pleasedeer, you names the only 2 bow only sheep units I am aware of - CO & Edmonton Alberta, both for rocky.
One day I would like to take one with a bow, but for now, drawing against 100:1 or worse odds will find me on the mountain with my .280. After I get one sheep, if I can afford to hunt 3 weeks, I would try bow.
There was a great article about, in my opinion, quite possibly the most dedicated archery sheep hunter in existince. It was in F&S and might still be on their website. This guy applies every year to the frank church wilderness of no return (Idaho). He has drawn 3 times (sheep are VERY scarce so tags are not to hard to draw there). He has gone in for about a MONTH, every time. One time he saw no legal rams. One time he was in with his buddy who was rifle hunting. They got into a group of 7 rams. (After 2 weeks) his buddy took a big ram and looked over at him and said, they are still there and one is a dandy - you want the rifle? Nope, he went after them with his bow, unsuccesful, and did not see another legal ram the rest of the hunt.
It is a GREAT article and this is one man I would like to meet someday.
Imagine all that time and never even getting within bow range. 3 one month hunts (that alone is rough). This guy is still applying to go back with bow, even after that.