combi bolters and champions

[Urdokadin]

Since boons rolls do not have the stipulation of killing a character in challenges I was wondering what people's opinion on taking combi bolters to try for precision shots with the reroll. It's only a point Less than a cultist upgrade but it makes your champion have the ability to take out sergeant level characters before a CC round. And any hits you do on overwatch you can maul people with. A nice little way to take out characters in IG blob squads.

Even more telling it says if you take a character out with the squad, like say with a plasma gun at rapid fire into a hive tyrant; so long as you cause a wound to be allocated (the wording says nothing of unsaved wounds just allocation) grants you a boon roll. This means you're always going to want your champion to do his shooting resolution in the wound pool first in the event your squad takes out those big nasty solo characters that run around.