It really all depends on what your looking for. I'm very saddened by the lack of support Pioneer is offering on their navigation units. I started with a 910 and upgraded to the 920 (for the bluetooth audio) and really miss being able to mod into the 910. I would be happy if they released either new maps or unlocked the bootloader.
Now on to your Question. Personally i have never used a JVC and by the looks of the model, it just seems outdated in a sense. If your wanting a unit with exceptional GPS and an IPOD intereface then you should really take look at the Sony XNV-770BT.
- Great ipod interface (with no need to buy additional cables)
- TOM TOM navigation built-in
If pioneer doesn't step up their game, i'm going with sony or a company that supports android.
I've tried the JVC just this past weekend and promptly sent it back to Amazon. I'm not thrilled with the my 930BT (my biggest want is clear BT handsfree and it does deliver there) so I've tried multiple models trying to find the perfect one. The JVC SEEMED like a nice unit on paper but was VERY disappointing in person. The screen had quite a bit of glare and you could visibly see the touch screen membrane in the sun. Next has to do with the interface, the screens and the maps all looked like ultra low resolution blocky detail. If you look at the product ads on this such as Crutchfields you can see this when you look at it and it became apparent when I went back to the ad. The GPS interface was so so and the options were generic feeling. It was in my car for less than an hour.
I've tried this JVC, pioneer X930BT, Sony 70BT (crazy slow clunky interface) and the kenwood DDX418. I loved the kenwood and would have kept it but the BT audio was absolutely terrible. People said I sounded like I was in a coffee can about 10 feet away. I tried with hours of kenwwod tech support and got nowhere. I might consider picking a high end kenwood as a last resort but Amazon doesn't carry these 
I wouldn't personally recommend the JVC.
