I would get that kimberwick out of her mouth, and I wouldn't even think about putting that slow twist in her mouth. In my opinion, both are extremely harsh bits and have no business being in a horse's mouth. That being said, I think a wonderful bit to use is the JP by Korsteel Oval Mouth Copper Loose Ring snaffle. I use that on my horse and he loves it. You can order it out of the Dover Saddlery catelog, at least that's where I got mine.
The reason your horse "doesn't listen" to the bits is because she has become hard in the mouth. Her previous owners could be to blame for this, riding with hard hands and such. So you need to work on very simple things that will keep you safe, like the one rein stop. Do you know how to teach that?
Also, work on being very slow, polite, and gentle with your hands. Don't be quick or jerky with your hands. That only upsets horses. See HOW LITTLE it takes to get her to do something. Above all, be patient. :)