We all approach arranger playing differently, Diki...to each his own...your way is not my way...and that's okay...I'm quite content with how I work...."piano" is just another color when I play arranger.
If 76 semi-weighted keys allow you to keep your piano chops, then that's cool, buddy.
They just don't cut it for me...not at all...they feel awful...the action on the G70 is nice, but it isn't anywhere near the feel of a weighted hammer action.
Carrying the extra keyboard, if it was a real weighted piano action(and around 25 lbs), would not be a chore...it would be a pleasure.
An extra stand? Pedal? Cables? Not much fuss there...wouldn't even need a mixer as the S900 has aux ins.
Maybe an extra 5 minutes setting up...no problem...I'm never in a hurry.
There is no substitute for the real deal....you play piano...you should know.
I'll wait...I don't mind.
Ian
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Yamaha Tyros4, Yamaha MS-60S Powered Monitors(2), Yamaha CS-01, Yamaha TQ-5, Yamaha PSR-S775.