The 3D compatibility is only a good feature if you plan on using it, I do not for see myself ever using it with the 3D technology that they are presently using.

So I would vote between the Denon and Onkyo and my usual preference is for Denon as I have never had a problem with the 2 I have owned and none of my friends that have Denon's have ever had any trouble either.

Jason
M80 v2
VP160 v3
QS8 v2
PB13 Ultra
Denon 3808
Samsung 85" Q70