Go Pro Suction Mount
I've got a bunch of hours on my Hero 4 using the original Go Pro suction mount. High, low, fast, slow and tons of aerobatics. No problem and very flexible.
Before I ever flew the camera, I loaded the case full of lead shot and flew it in multiple positions - wing (top and bottom), vertical stabilizer, belly, and horizontal stab. That think latches on like crazy. A word of caution here. Use the official Go Pro mount. The cheap knockoffs don't cut it. The Go Pro mount uses a locking suction device and it works really well. Give it a nice clean surface and you are good to go.