Old or new Kato Power Pack

[TFW]

I tried some of my powerpacks with my tiny selection of Kato rolling stock and to my surprise the lcos run very nice even with my old Spectrum powerpack. In the past I seldom used it because my trains did run better with my controllers with feedback. However my two new Kato locos and my new Koto EMU seem to have very nice running capabilities by themselves and run good and silent with my simple Spectrum power pack without pwm or feedback. The slow running capabilities are even better with feedback control but at the cost of a bit of "humming". 

So I wonder whether the Kato SX controller with pwm is a good idea. If I want silent running, would it be better to buy the older version or run the trains with pwm as silent as without and it is only feedback control that makes them hum? Please advise!

 

Thomas

[Yavianice]

If you have interior lighting then I recommend the SX. If not there is no reason to switch.