I'm less devoted to green paint that just about anyone. I run a certain amount of Deere stuff simply because it was cheap and available. On balance I see a lot more PT Deere harvester than I've ever seen of NH pull types unless you take the 717/718 into account... and in that case you deserve what you get if you buy one.
IH was a complete non-entity around here in terms of harvesters. Pretty much a non-entity in every other department as well.
My personal view is that you go with the one that's most economical to purchase/maintain. You'll learn early on with a Deere that you keep a bunch of spare knives on hand. You make a point of doing careful inspections of feedroll bearings annually and keeping a set of them on hand after 3-4 years of use and when they whoof their cookies you change them. You keep a spare row crop head around or at least a spare chain or two. Outside of that you're not apt to need much in an emergency situation and if you do the dealer won't have it anyway... so then you get it drop shipped from the depot anyway. I really don't see what the big deal is about the dealer. The way most of you go on, you'd be out of business tomorrow if you had to deal with the support we have around here.