There are ram ball solutions that are better. Wunderlich and nippy normans, telfreizer (not sure if that's spelt right) all do mounts that go into the existing stem hole.
I have one of these for my GoPro, it goes inside the fork thing and goes tight no change of it coming loose etc, get many attachments for these i.e. Go pro, sat nav, mobile phone holders etc hope this helps.
I have covered about 500 mile with my go pro I haven't had any issues, doesn't move around or nothing. I had a securing wire on it first 200 mile incase. I would highly recommend this product pal.
Im on it cheers. Mounting a drift camera. The 1 i bought is great in terms of positioning but like others have mentioned the yoke nut doesnt look very durable. But that will do the trick and i can attach the 1 i bought to it. Job done