I've had the same speaker system for about 25 years...two Yamaha MS-60S with the then newly developed AST ( Active Servo Technology).

If I need a huge or bigger system, I rent one, usually a pair of Bose L1 with subs or a Stagepas 600i/500 and add the rental in my fee. I can also use the MS-60S's as monitors if I wish.

I have feeling the Tyros4 is a long term keeper, but maybe not 25 years.

Ian