Power cord supplied with Luxman L-509X Integrated Amp

+1 badger_erich! Power cords, fuses, power conditioners are simply there to extract wealth from one party to another party! 

Good grief what a bunch of ridiculous replies.
Thunderball, there are thousands of products that are engineered in such a way that they do not require a grounded plug, the term for any item like that is 'Double Insulated', so stop worrying about it, Luxman isn’t trying to electrocute you.
My experience with my L-590AX amp is that the supplied power cord is quite good. At one point, I replaced it with a $200 cord from DH Labs, and I couldn’t hear the difference. Later, I bought a more expensive power cord, near the top of their product line, the improvement was quite noticable.

Thunderball

, there are thousands of products that are engineered in such a way that they do not require a grounded plug, the term for any item like that is 'Double Insulated', so stop worrying about it, Luxman isn’t trying to electrocute you.

I’m not worried about Luxman trying to electrocute me, I am worried about electrocuting myself or frying the amp if I replace the cord with something else.

Think about inbuilt power cords for a second - used with many different kinds of electronics. You wouldn’t think of removing those cables and resoldering "audiophile grade" cables, now would you?

Yes I would and did and so do many others. Each and every component had a dramatic improvement in sound,with the exception of my toaster and microwave. 

Changing to IEC is an easy mod to make to a component, be it an amp, pre, CD or DVD player to get a good bump in sound for very little money. (Given you have a good cable already)