The suction cup actually works fine for me. I try to minimize the GoPro 3M perm mounts if at all possible. The only perm mounts I have on my bike is on the swing arm (left side) and under tail; all other shots I use my suction cup with all extension brackets possible...lol
I don't have pics to show, however feel free to check out my vid below for examples. Try your best to include a portion of bike within the video, with nothing in the foreground, you tend to loose the full effect especially when leaning.
Good luck and post vids from your outcome.