Sensation is absolutely safe and there's no need for any fixes or switches or whatever. Ivan did a great job on it.
Yes. My question was kind of dumb - before I read the previous posts closely and realized it was to override the power switch on the amp. Obviously if the soft start is working properly on the Sensation (which is seems to be) then no switch would be necessary.
BTW, how long is the soft-start delay on the Sensation? I set up a battery supply for it and it works great. However when trying to A/B the 130W switching PSU with the batteries (ie, turning the amp off, turning the main power off, swapping PSUs, turning the main power back on, waiting for the single red light on the front, then powering on), sometimes the amp would fail to turn on from standby mode. This seemed to occur predominantly when hooked up to the batteries. Waiting a few seconds did not seem to help, but when I powered off and powered on the main power switch at the back, everything would work. This seemed to only occur when switching from the 130W supply, but I will have to investigate further.
But I guess that turning the main power switch off and on is probably not the best for it... (so maybe trying to A/B power supplies is not really a good idea)