After years of fruitless searching and a not inconsiderable amount of money spent, I've finally found a good, cheap, 1080p waterproof action camera.
I get a lot of emails from people asking what action camera I would recommend for occasional use for paint-balling, mountain biking, etc - that costs around £50. Prior to today, my response has been that the cheapest camera I could really recommend was the Liquid Image Ego, but it costs£100.
If your budget doesn't stretch to £100 then there are very few action cameras to choose from. Perhaps the best camera from a very short shortlist is the the RD32II, but it suffers from a substandard mounting system and a non-standard video format.
The SJ1000 changes everything. For about £60 you can buy a camera that is capable (under the right conditions) of producing video that rivals cameras costing over four times as much. I'm not suggesting that people throw away their GoPro HDHero 3 Black Edition cameras and get this instead...but if you are on a limited budget or don't see the point in spending £200+ on something you only plan on using a couple of times a year then this might well be the camera for you.
You'll have to do a bit of experimenting to get the mounting options to fit your requirements, but it's definitely worth the trouble when you see the video quality that you can get from this small camera.
WANT TO BUY ONE?
I should mention that I haven't shot many 720p60 clips...and you'll only find 1080p on the bike.
The only thing I think that I forgot to say in the video was that when using it as a car DVR there is no gap between clips (as you expect nowadays)...in fact each clip repeats the last second of the previous one just to be sure.
UPDATE - 10 June 2013 - Answering a few questions.
First some bad news - The 720p60 mode turns out to actually be 720p30 (every frame is shown twice). I should have spotted this earlier, but I had only been testing the 1080p30 mode as that's the one I use. iMovie always converts 720p60 to 720p30 so that's why I didn't notice it before...apologies for that. Here is a link to a fast moving 720p clip I shot today.
Motion Detection mode - When this is on, the camera records 10 seconds of video and then stops until it sees another movement. If a movement occurs during the 10 seconds when it's recording then the timer is reset and it records for another 10 seconds. This way if the movement doesn't stop then the camera doesn't either....hope that makes sense.
The camera should be able to be mounted the right way up in a car if the correct mounts are combined....this is demonstrated in some of the ebay auction photos.
File Sizes: 10 Minutes of video takes up 1.2GB in 1080p or 1.07GB in 720p modes.
The case floats in water and on it's own weighs 66.7g.
The camera itself is 7cm tall, 4.5cm wide, 3 cm thick at the bottom and 3.5cm thick at the top where the lens makes it deeper.
The timestamp can be switched off. I turned it off for the Night Time Driving clips and show this option on-screen 19:57 into the video.
I think the manufacturer may be a company with the snappy name of Shenzhen Hongfeng Century Technology Co. Ltd.
BATTERY LIFE is 2hrs 15mins (Could be 2hr 30 mins or more with the screen off)
UPDATE 29 August 2013 'NEW' FIRMWARE!
I know a few people have been waiting for this - so finally here is the updated firmware that fixes the screensaver bug. If the fact that the screen didn't automatically blank out wasn't an issue to you, I'd suggest skipping this update. If you want to update the firmware, you can download the file from the Files & Drivers Page. Updating it is very easy, but just in case you are unsure...here's a quick video. Beware, if you somehow kill it, you are on your own.
Update 27 Sept 2013
This is a six month old review and a lot has happened since. You'll find the cases are improved, possibly the mounts too..and you now have the ability to turn the camera on when it's inside the case due to a different button arrangement. The current crop seem to have a 90º lens rather than the 140º on my camera. That means no fish-eye - but less FOV. I'm not doing any more videos about camera this but.....PLEASE READ THE COMMENTS...before posting a question that's been asked countless times before, it's the least you could do for all the kind people who have given up their time to elaborate on the features of this camera and posted their findings in the comments. I'll give you a starter...NO IT DOESN'T DO TIMELAPSE...The way you can tell this is because there is no option for this on the screen when I go through all the menus in the camera...and it's the kind of thing I would have mentioned. I tend not to mention the things a camera doesn't do because we would be here all day....you can't clip your toenails with this camera, it can't be used as a flotation device, it won't take x-rays etc.....