99% of guys have looked up a Barbie's skirt. 1% of blokes are liars.
I'd say you got lucky, considering that Customs have known how to spot Megatron in robot mode since 2007. I personally wouldn't recommend using the old "send it in robot mode" method anymore. Best bet (for those of us living outside WA and SA) is either to acquire a permit, or if you live in a state where the toy is still illegal, contact your state's Police Ministry.