Howabout, 1)you do your own research. 2)Find out exactly what apples and oranges are different. 3)Propose them on here and ask us to offer why we chose apples or oranges. Here are a few and why.
Speaking for the 3320:
I can say that in my case, split brakes are definitely a necessity. Bring your Kubota over to my place and I can put you on a slippery slope predicament where without r/l wheel brakes, you'll go sliding over into a ravine. I can say that while maybe Rat can handle using cruise control while toe-ing the brakes, I'll bet Kubota doesn't recommend it. I use mine when I'm in a tight jam and sometimes mowing but not usually where I could be in a "cruise control" situation. These are just excuses for Kubota's lack of insight on the brakes. Maybe they all have their kids riding in their laps and teach them to brake for them.
The Load match hydro is another feature that you can't discount just because you've never used it. It works excellent for FEL work and mowing pastures where you encounter different thicknesses of grass. It will slow the tractor when you hit a heavy patch of grass.
The dual pedals are far superior IMO. You can rest your heel just like about a billion automobiles have their gas pedals.
Yellow seat doesn't get hot as tarnations in the summer sun.
Grab handles on each fender. Get your machine leaning over in a ditch and you'll understand the importance.
Rubber floormat is more comfortable. And it doesn't show the orange paint worn off.
Bigger fuel tank.
Hydro whine is standard on any hydrostatic. Just a matter of whats wrapped around it to deflect the noise.
Stronger 3 pt lift capacity.
Joystick location. Has Kubota improved theirs yet? Don't know but it was annoying when I was shopping.
If you ever get a back injury, you can get a drive over self connecting mower deck for the deere. Might be the last thing on your list. I hope no one ever gets a back injury but it would bring it to the top of my list if I did.
You can buy deere parts online while sitting at home in your skivvies and sipping on a barley pop. You can check inventory of your closest (and next few closest) stores. The parts price is posted so there ain't no jacking it up higher at the dealer. You might have to pay some freight for special order heavy or big stuff to your dealer. My dealer will put stuff out back for me to pick up after hours. "Just come pay us when you get a chance."
Anyhow, if you don't think that comfortable ergonomics, added hydraulic flow, and the things above don't add up to $4000 go buy the Kubota. I personnally think if you list whereabouts you live, some of the folks on here can point out a good deere dealer. BTW, the Kubota dealer I went to was higher than the comparable deere. Goodluck with whatever you end up with.