Hey all, I've also got a G1WH and thought I'd share my experiences thus far.
I bought two units in late March (2014) through eBay seller "1gobuy", who has very good feedback (99% positive). The units were advertised as "Full HD1080P 2.7" LCD Car Dash DVR Camera Recorder G-sensor G1WH Novatek NT96650", so I figured they were genuine.
One unit for was me and the other was for a friend. We both bought 16Gb SanDisk Ultra Class 10 Micro SD cards to use with the cams. My unit has been working well, with the exception of sound recording being very low, as noted by other uses. My unit came with firmware version 2014.0108. I record at 1080p with HDR enabled on a 10 min loop cycle, and all is good.
My friends unit however has started having some problems. She informed that sometimes when she's driving the unit just automatically turns itself off. Since then things have gotten worse, in that currently the unit powers on and the screen displays what the camera sees, however all the on-screen information is now missing. ie, battery icon, resolution, etc. All that the screen displays is what the camera is seeing.
I've messed around with the cam a bit whilst she was driving to try figure out the issue. The unit remains connected to the cars cigarette lighter power source all the time. The only thing the camera will do is power off and on by holding the power button. None of the other buttons do a thing. However, I noticed that once I removed the SD card and power on the unit the on screen display returns as normal, along with the camera image. However at that point the camera presents a message about inserting a memory card and then just powers down again.
As such I'm guessing the problem is SD card related. When I get a chance to troubleshoot it I'll try formatting the SD card on a PC and see if that has an effect, as well as try a different SD card. I also read that having a 10 min loop cycle can cause problems with these cams so I'll chech that too. I'm not sure what firmware version her unit is running but I'll check that also and maybe try a firmware update if necessary.
When the G1WH is working properly I'm actually very impressed with its performance, especially given the cheap price (only cost me AUD$70 through eBay). The video quality is great, and the wider FOV makes a huge difference compared to my previous cam. I also own a GS1000 Orange Menu unit, and compared to the GS1000 the G1WH has a much wider FOV and much clearer video. The GS1000 has better audio pickup, but it's not exactly fantastic either.