The point is you are much safer with 110v because it the secondary of the transformer is grounded at mid potential. this means there is 55v between you and earth potential instead of 230v (nominal voltages used for illustration).
nothing to stop you plugging your transformer in through an rcd aswell.
As you may know an rcd does nothing to protect you if you hold the neutral in one hand and the phase (line) in the other, wherein there is a 230v potential through your body. with 110v in said scenario there is a 110v potential.
but as we know it is mills that kills though volts makes you jolts.
however the greater the voltage potential across your body the greater the milliamps which will flow. You only need 40 of those before you are recycled by worms.
Don't be a fool, be safe.
I always buy 110v tools, it's me I'm protecting.