Here's the way I see it....
Your components power supplies all need to be compatible with 220v input. Many products are not and would require modification at the factory to be compatible with 240v input.
Also, it is my opinion that only current hungry devices, like big power amplifiers will see big gains going from the higher voltage.
For source components, I'd say feed them with balanced power from something like a BPT, ExactPower, Equitech or PS Audio units.
Just my thoughts I'm sure others will disagree.
Regards,