I've had the H264 A8 version in the car for a several months now. Some comments and observations...
Got it for about $41 on 3/8/2013 from wonderfull003 on ebay. Shortly afterwards, the price shot up to $96.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=251202727212
At this ebay site, the camera is sold out but there are some useful photos
http://www.ebay.co.uk/itm/New-HD-Sm...-sensor-/110913841519?clk_rvr_id=463231210746
The camera seems to be available for $43 at
http://www.aliexpress.com/item/2012...sor-120-degree-wide-angle-D-A8/566785095.html
I like this version much better than the original one which had no mic switch. The daytime video quality is quite good. Night is not great, but acceptable. The camera is very small and unobtrusive. Also, it mounts directly (semi-permanently) to the windshield; no need for bulky mounting contraption.
Occasionally the camera just decides to shut down whether it's warm or cool. If I turn off ignition and restart, the camera runs OK.
The audio was scratchy and noisy. After disassembling the camera, I decided that I would try replacing the microphone. Finally located an exact replacement at
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=190690560316. That solved the problem, though it requires some very fine soldering skills.
To disassemble the camera, note that the circular trim ring on the left end of the camera just pops off, revealing 4 screws. Caution: when you go to remove the camera housing from the mounting ring, a spring-loaded ball bearing will slip out and fly across the room. Lay a cloth over the camera to catch it.
When I first stuck the camera on the windshield, the picture was noticeably off level. In order to reposition, I first located suitable double-sided tape at
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=400435816620. Using a single-edge razor blade, I was able to separate the old tape from the glass without damaging the plastic mount. Then I remounted the camera in the correct position with new tape.
I use a Sandisk 32GB Ultra Micro chip which gives me about 10 days of recording before it automatically erases older files. I have not had any problem with losing date/time as some others have reported.
Altogether, I like the camera for high quality picture and very small size. Definitely worth $40-$50, but $100 is stretching it. I am actually considering getting 3 more of them for full wrap around coverage. [Those plans are on hold -- see below.]
[UPDATE - June 28]
Now that summer is here, I see the camera goes out of focus when the car is parked in the hot sun. I tried shading it with a small piece of cardboard, but it did not help. Once things cool down, the camera returns to proper focus but this is a serious problem.