Which Arranger Keyboard Would You Say Has Biggest Learning Curve?

Usually your first one.

I never had a problem with any brand, but from what I'm told by others, they're all, technically, pretty much the same. Just different terminology for the same menus. Some may take more steps to accomplish the same goals, but the secret to learning the operating system of any arranger keyboard is to sit down with the instruction/user manual next to the keyboard and go through each and every feature, step by step. That said, most of the manuals are poorly written and constructed, therefore, the various tutorial forums, such as www.psrtutorial.com, which is a Yamaha site, can provide a great deal of assistance in decreasing the steepness of the learning curve. And, forums, such as this one, can often provide answers for perplexing questions when you feel like you're beating your head against the wall with the manuals.

Hope this helps,

Gary

Gary is absolutely right. I have owned Yamaha, Roland and Korg arrangers and each has its pluses and minuses. You can sit down and play something terrific with the stock styles and sounds of any arranger. Getting familiar and comfortable with a particular operating system is a personal matter depending on what your wants and needs are.

difficult > easiest...........

KORG
KETRON
ROLAND
YAMAHA

I would put Roland easiest, then Ketron, then Korg and THEN Yamaha.
I have answered probably a thousand questions on Yamaha OS. (Of course there are lots more people playing them.)
I'll bet I have had to explain how to save a registration a hundred times, and Gary probably has done it 10 times more.
For the uninitiated, you save the registration, then must save the bank, AFTER you tell it what parameters to save and ignore, in two totally different menus.

Don, as usual, is right about the progression of the learning curves. All of them are a lot harder than they should be for the task they perform.

Gary

Unfortunately, the easiest - and most advanced for its time - KB I've ever used is no longer made - technics KN series ...