I love my suction cup mount. It WILL fall off under moderate pressure, sub, turn sub, anything like that. Always use a lanyard with the suction mount and it wont work for hard abuse. It's awesome for racing type stuff. I've put it on my gunwhale and everywhere else on my ski. Just always always always use a lanyard.
I haven't had any problem with my sticky mounts. I don't do 20' nose stabs, but I haven't had any issues with flat water subs or similar. I have them on my helmet. and they are great for that. You always mount it in the same place every time, so it doesn't matter. THey have curved and straight mounts. Curves is what you will use for almost everything.
I have a helmet that doesn't have a visor. I have a sticky mount all the way forward. I use several attachments to make the mount about 6" long, and the camera looks back downward at me. This is a great angle. You can see everything you are doing with the bars, foot and body position. It's a great way to critique. I really want to get a second go pro so I can run this camera angle synced with one on the nose so I can see when I go into the corner and how I set up for it, or for free ride same thing, when I hit the wave and how I am setting up for it. I have been trying to learn flatwater 180s and I had my suction cup mount on the nose looking back, I felt like I was turning the bars a lot but it turns out I am not turning them at all (compared to what they can turn). The other camera angle I just described would show exact body position and steering etc.
I have the handle bar mount but only use it with my quad. It bolts to the frame, the grab bar, etc. I want a roll bar mount for my nerf bars, but neither of these have uses on a ski.
If you don't have a suction mount, get one. Just lanyard up and find all your favorite places to mount on the ski.