The Go -Pro
I don't think that there is anything better for the fisherman at the moment.
Ok, it is not exactly a tiny piece of equipment when compared to the secret agent type sized device that would be handy for us fishermen but then again it's by no means overly huge in it's basic form with waterfproof housing and can be worn on the head via a harness all day without much issue.
There are also a few attachments which can be easily fitted to possibly enhance your days filming/ fishing eg. the battery pack, LCD monitor, flotation pack, etc.
The first two of these IMO all add just that little bit too much weight making head mounting of the Go Pro too much like hard work & as said head mounting is my preferred option. Chest mounting should not be an issue with these add ons.
Even in the confines of the tube changing batteries over is a very basic task so my battery pack has been relegated to the house being used as a battery charger via the mini USB port.
I've never really seen the need for an LCD display either -some form of Wi-Fi monitor, absolutely, but due to the fact that when it's on your head, on your chest or even underwater (were talking on a pole when you are in a boat, on the bank, etc) then you either won't see it or have it add any real value, you roughly point and shoot and due to the varying wide angle settings available decent capture is almost guaranteed. Have a few test shots though on your preferred mounting style and angle setting so that you have a feel for where the housing should be angled, 'too much sky' looks poor in my opinion.
Video quality is also very good and the rendered file on your PC is really quite amazing.
Editing software.......I use Cyberlink Powerdirector 11, only yesterday I was having a look on the Net to see if there was anything reviewed as better than this but again it is apparently top of the field for the layman, this said I have had a few issues with the program hanging up and apparently this has been noted by a few users and the upshot appears to be that you should have a fairly decent computer system to cope the amount of data that some productions can accumulate.
I'd think there are some very basic and free programs that would work perfectly well if you just wanted to produce a title, some footage and the odd transition.
I'll not change my Go Pro for the slightly smaller and lighter Go-Pro III, hopefully by the time there is a version IV it will be the beast that we are all looking for.
Vivitar, never owned or used one and the fact that they seem the preferred make for home shopping channels would make me steer clear by gut instinct alone, your mention of the video quality seems to confirm my concern.
Iain