I guess playing just about EVERY night, and sometimes another time in the day, I feel like I need to change for the sake of change sometimes.
I try to buy my arranger at a great price, then sell it before I take much of a loss, if any.
Almost every change I've made has been an improvement in some way, with a couple of sidesteps along the way.
I could easily be using a PSR2000, which I DID use for several years. The public couldn't tell any difference if I did, but I could. The S900 has improved storage, improved navigation, ability to store text files, color screen, bigger screen, better speakers, better buttons, corrected vocal harmony settings, a great WAV (forget MP3s!) recorder--I could go on and on. It sounds pretty much the same as every Yamaha from the PSR8000 to now though. The S900 allows me to leave the laptop and the external recorder at home if I choose.
Another thing, I tend to be very gentle with my keyboards, but moving them as often as I do, and playing them as much as I do, they won't last forever. I want to move on BEFORE I have problems. Most of the time, around tax time, I start being able to justify another purchase, IF there's something that appeals to me.
Right now, the only thing I can think of is Ketron Audya, and that will be a while getting here. Maybe NAMM will bring some surprises--who knows.
Worst purchase? I suppose I bought the Korg PA800 too soon, before it was ready for the public, but I don't plan to revisit that because there is no place without 200 miles to see and hear a new one. I spent weeks trying to get it to sound good, but I couldn't.
Right now, the PSR S900 has more bang for the buck than anything I've seen in a long time, maybe since Technics KN2000.
A KEEPER? For sure! I could use it for years, but I'm sure I won't, because I don't choose to!
But I'm happy. For now.
If only the G70 didn't weigh so much . . .

DonM