I got a Ghost HD after borrowing a Hero 3 black for a week, and hating
it. The lack of LCD screen and rotatable lens meant it was trial and error, reviewing footage on a latptop to get the thing actually filming what I wanted for each new mounting position, and by the time I got it right, the bloody battery went flat. If you're a pixel-peeper, the GoPro has the better image detail (although IMO it doesn't reproduce color as well, everything seems kind-of 'tinted'). But when it comes to actually watching whats going on
, there's really no practical difference. Most folk I know record in 720p/30fps anyway to save card space. WTF the point is in 4K recording I have no idea.
The Ghost is great. Comes with everything you need as standard (unlike the GoPro). I got mine for $400 flat with a 32GB card (less than the GoPro). The flashy remote is great, lets you know what the cam is actually doing (unlike the gopro). Water/dust/ice/mud proof without a case (unlike the gopro). Battery life is a consistent 3 hours (double the gopro). The tagging feature saves trawling through hours
of footage, but never risks missing something unexpected because you weren't recording to save space (unlike the GoPro). However, low light footage is pretty poor. Anything at night is very noisy. GoPro definitely wins there. But in terms of usability, the Ghost wins. Out of the box, no screwing about with waterproof cases, laptops, extra LCD screens, steroe external mic adaptors, constant battery swaps. All you need is a USB cable and a cig socket charger, and you're good for as long as you're on the road.
In a nutshell, if you're after production grade footage at the expense of everything else, and you've got the laptop and a box of batteries in the support truck, the GoPro is the go. If you're after an easy to use cam for a few days on (or off) the road - the Ghost is fantastic. Usability is its selling point. You don't even have to think about it to get the footage you want.
On the microphone/wind noise:
Both the GoPro and the Ghost have sucky built in mics. ALL built in mics on most things are awful, especially when they need to be weather resistant. At least the Ghost has a standard stereo input plug - unlike the GoPro, where you need a USB-stereo accessory....which costs extra.
I got an old combined earbud/mic headset for Skyping, worth about $10 from DickSmith, and butchered it so I had just the mic. After some experimenting, I found the best setup was to run it in the mouthpiece of the helmet. A bit of artfully placed electrical tape to bulk up the stereo plug, it's snug around the rear port in the Ghost body, leaving it rain-proof. Gives stereo sound, clear voice and cuts the wind noise down to a low background roar at 110kph, keeps the exhaust note and other outside noises (people nearby) audible. Downside is that your footage seems way less hardcore when it includes a soundtrack of you singing along to Florence and the Machine. Which is why there's no Youtube demo clip
But here's some pics of the setup. I've also modified the standard clip with a dremel tool and a spring, to give the cam a notched rotation, so I can change viewing angle mid ride without taking my eyes off the road. Took about 15 mins, can post pics if folks want to duplicate it.
The white cable/dongle is the mic for the Ghost, the foam bud ifs for my UHF/starcom thingummy.
Extra cable gives a bit of on-the-fly-rotateability.