We have been running a 336 for over a decade now and it has been fine for us. We are doing around 3,000 bales a year and not having to push the baler at all. The wider pickup on a "7" or "8" series JD baler would be nice, though.
I have nothing against NH balers other than the local dealers are not the greatest to work with for sales or parts. For me the service I get from my JD dealer pushes them ahead.