I'm curious about your statement that the Tyros 5 is:
"at best a $3,000 arranger keyboard"

I presume you are referring to a 61 key model? My Tyros 5/76 cost me (pound/$) $5500.

Around 1994 I paid $2675 for my Kurzweil K1200 Pro/76. My 2013 cost of $5500 seems good value when compared to 1994.

YMMV

Ian