330CH, 3800FU, 900HD Combo, - nice discrete design, - something what many people are looking for.
Drawback is a glossy finish. This attracts attention from thefes and leaves finger-prints.
Also drawback is in mount / bracket design. Why it is positioned on the very edge / side ?
Having 3800FU in the past I had a bad experience with wobbling / vibrations, so I had to do my own DIY bracket adding it to opposite side to stop vibrations.
This is very basic physics that if you hold some heavy horizontal object from one end, - then other end become non stable. If you hold object on the centre, - then weight distribution is balanced and there are almost no vibrations. I dont know why your R&D department developed such an non-practical mount solution. What for they get paid ?
My opinion and questions:
3300CH, why only HD + HD, why not FullHD + HD?
3800FU, - this one I had personally, I like some things I mentioned earlier, but why such a low bit-rate ?
Defender, - this deisgn is sort of OK if compare to what other manufacturers offering now on the market, however its not exactly what many people want ( not discrete solution ), but rear camera design is nice and sleek, I like it.
Question again: why HD + HD ? - this is in the past 2012y. Now 2014, many go over to SuperHD ( 1296p ), but you could go at least Front FullHD + rear HD, if not both FullHD + FullHD.
Iroad GT, - this is actually can be mounted discretely, despite first looks bulky. I have BlackSys CF-100 for 1 year, it is exactly same design and I must say it for sure can be mounted discretely, not fully discretely how I would like, but still better than many other Korean 2ch ( except Blackvue lipstick / capsule style series ).
Questions again: Front HD and rear VGA. Why such a low specs ?!
For same price can buy Blacksys CF-100 with front 1080p SOny Exmor ( 14Mbps ) and rear 720P ( 4-5Mbps ), which combined produces quite good video quality compare to what is now available within 200-220 usd 2ch dashcam systems out there.
AEV WIFI, 720p _ wiFi, horizontal flat design, can be mounted quite discretely, so from design point of view its OK and for 99usd for 720p + WiFi I think its a fair deal, but as you are using a 2Mpix CMOS, - why not go with FullHD resolution ?
T35, Front FullHD + Sony Exmor, - great choice on CMOS and I believe it might give a good video quality, because I liked 3800FU from your products. Colour balance and night performance there was good, however bit-rate was low. If bit-rate is also low on this one, then it's not such good "improvement". Also rear camera used on T35 is only a VGA, - not a good sign for 2014. It must be at least 720p rear.
I know you probably dont like my criticism, but I just wanted to be honest to you regarding what I think.
I also know that there are different market need in Korea, but if you plan to go outside, - you have to relay on those market needs and overall competition in order to progress. And only by listening to criticism, - you can go further in products development that end customer would like to pay hard earned $.
Its a good sign that you are not afraid to register personally on public forum and talk directly to end user. I am sure - the more time your R&D department people spend on forums, - the quicker they get the overall picture on how should look next successful product you plan to produce.