Circle Hooks

Took a friend to a good spot with a group of reds. After a hook up with a “conventional fly” I had him try on a clouser tied on a circle hook. He had three good takes, with slow set of the hook, without hook up. I had a weed guard on the hook an think that this probably played a role in the lost fish. However, I do have reservations on the circle hook. Has anyone else tried to tie flies on circle hooks? Success? Failure? Thanks.