I ordered the JVC KW-AVX840 last Thursday from Sonic Electronic and received it the next day. This is the fastest delivery that I ever seen.... Thanks Sonic Electronics!!!

Regarding the JVC KW-AVX840... I had it professionally installed at Best Buy... The head unit itself is really good... I like the screen size and the image quality. The sound quality is awesome!!! Much better than the stock radio... The touch panel is really responsive... I do not see any lags at all... I like all the functions on this HU. The only issue that I'm having is as follow:

I was not able to get any video and sound to display through my wife's iphone 4 (using JVC KS-U30 cable)... I than tried setting "AUDIO INPUT" to "A/V IN" and "VIDEO INPUT" to Ipod... This allowed me to display both video with sound... But this only worked when I used the "External Mode" after using Motion X software... I have to close out Motion X software first and than go to play video. It will not work if I don't use Motion X software first or if I have my Car engine turned on (with emergency break on). I even tried rebooting my iphone 4 and turning the car engine on and off... I think this is a really strange behavior.

I also have Voice Command issue... I also tried using my Android phone and it still have the same issue. It does not pick up the correct voice command... If I say: "Call Art Cell" it will dial a different number. I see this issue on my wife's Iphone 4 and my Android cellphone. If I use the voice commands on both phones by them self.. it works just fine... It was able to pickup voice command correctly. But if I tried it again using the microphone provided by the JVC head unit, it will not pickup the correct voice command.

I also had a backup camera installed onto this HU... it works perfectly!!!

I bought this HU for the bluebooth hand free calling and music streaming, and the ability to connect a backup camera...

I really think this is a good HU... But I wish that it would be easier to setup... It took me three days to figure out how to get video and sound to display correctly using my wife's iphone 4. I also wish that the "Voice command" can pickup the correct commands...