My first arranger was Yamaha PS30. It was the first Yamaha arranger with full sized keys.
Pretty soon got a PS 6100. Then 6300, PSR 500, 510, 620, 740, 8000, 9000, Tyros, 2000, 2100, S900, 910, 950, 970.
Also along the way Technics 800, 1000, 3000, 5000?. Roland G800, G70, E50, E800, EA7.
Korg PA80, PA800, PA3x, PA900, PA4X.
Also Ketron X1, SD1, SD5, Midjay, Audya, SD7.
Also a Peavey made by General Music for them.
I'm certain I'm missing some.
That's 37 so far, if you don't count owning a couple of the more than once.
The early ones, I midied to an external drum machine and used synths and/or modules for lead sounds. The first one I could use the drums on was Technics 1000, but still used a drum machine with it when needed.
The PSR8000 was way ahead of its time. It was first to have a usable vocal and harmonizer.
Later model Technics had as good or better drums than some current Yamahas, but not nearly as varied. Technics had many features that the others didn't have for several years. Registrations, midi to style conversion, great style creator, Multipads, usable guitars, pianos, organs...all very good for the time.
The best I've had, as far as sound and features, would have to be PA4X, Audya, G70...not in any particular order. When I first heard the X1, it totally blew me away. Sounded like a live drummer and the vocal sounds were great. It had the variation and fill buttons on the wrong side of the keyboard though! Ketron operating systems were archaic until the last few years. Pretty good now.
The ones I kept the longest were PSR 8000 and 2000/2100. Also used Roland E50 for a couple of years, which as you can seen is rare for me.
I just counted 37 arrangers and I'm certain I've missed a couple.
Won't be many more that's for sure. I can see one more totl model if I live long enough.
If not Genos, then PA5X, if that's what they call it.
But who knows, right?