I'd say that it takes quite a lot of time to get adjusted to a new keyboard. Plus, all the excitement and wondering "did I make a smart choice or should I get my money back" works like a major distraction, at least, in my case. It took me about a month to get used to PSR-S950's speakers after playing PSR-3000, I even thought that a left one was louder than a right one.

At least, PA1000 is much lighter than PA3X is.