Well, since I'm apparently regarded as an authority on the subject...
I have the HD Hero 960. It's one of the more basic models. The package I purchased came with a head-strap mount, two stick-on mounts, the waterproof case, and one battery. Each battery lasts about 3 hours.
I would also recommend purchasing extra batteries. You can get off-brand batteries for much cheaper through Amazon. You will also need to pick up an SD memory card. I have a 32GB card, which holds about 8 hours of footage.
The camera does have its limitations. The microphone isn't the greatest; it will pick up your voice just fine, but anyone more than a few feet away will sound very quiet (especially with the waterproof door on the case). The audio can be boosted post-production with a video editing program, but it rarely comes out crisp. Also, it does very poorly under low-light conditions, but most daytime outdoor footage comes out fine.
Check out the GoPro website and look at the models to decide which one is the best for what you want to use it for. I'd avoid buying any accessories a la carte until you get the camera itself first.
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Now the sun is just starting to climb up over the treetops,
And it's gonna be a beautiful day, that's plain to see.
But I won't be around at all, so don't even bother to call,
Cause on a day like today there's one place I gotta be:
GONE FISHIN'
Fishing with LardAlmighty on YouTube
