Then you didn't have the right chokes and gave up on a good shooting gun more than likely.
I suggest you tell your friend to try to find a Star Dot choke for his 835 or a Pure Gold .670. Indian Creek, TruGlo SSX .670 are other good shooting turkey chokes to try. Don't know if you were trying turkey chokes or what, but the 935 will shoot. I have seen some great patterns from guys that own them. They have the same exact .775 bore dimension.