A 702B owner
I've had a 702B since Nov. and have experienced both the good and bad.
Starting with the downside -- JVC service is horrible. It took me two months and many, many phone calls and emails to get a defective unit replaced. It had to be replaced because no local authorized JVC repair center could do the work.
Now that I've gotten a new unit and had it for some months, though, I will say both audio and video performance is quite good, at least for my purposes. I am not an audiophile, but do listen to a great deal of 2-ch. music. My video use is a 50/50 mix of DVDs and HD cable.
Audio -- what I would consider it a natural sound with great presence for acoustic instruments and vocals. For reference, I replaced a 6-yr-old mid-level Yamaha AVR, and have found the JVC to be an improvement. It's connected to Axiom TM 22s in the front, QS4s in the rear, a Cambridge center speaker and a 12 in. Infinity model I can't remember the number of. Like I said, nothing fancy.
Video -- two HDMI inputs, one out. Great convenience and, for me at least, they work well connected to a cable box and Sony HDMI DVD player. On SD analog channels, the receiver "upconverts" 420i to 420p with a Faradouja (spelling?) chip, and it makes a very large improvement for those channels (which were awful).
Misc. This second unit does not run exceptionally hot. I tend to dislike digital sound processing, but the new Dolby and DTS Neo options are interesting. I haven't hooked up two more speakers for 7.1.
Oh yes, the wireless USB recevier is really a toy and not useful, and the manual is even more useless.