amazon.com or local amazon

Hi I am adding amazon in addition to an existing website that used to only have adsense on it. The site is a .ch domain with Swiss traffic. If you visit amazon.ch it redirects you to amazon.de homepage. But if you check the topsites in alexa it looks like amazon.com is more popular in Switzerland then amazon.de Which of the amazon sites do you think I should link too?

I also have a .nl domain with a similiar situation where amazon.nl currently redirects to amazon.co.uk but it looks like amazon.com is more popular with the Dutch then amazon.co.uk?
Thanks

So you don't need a plugin to redirect to a "local" Amazon site, correct? If you're on Amazon ch, it will redirect customers to Amazon uk by itself, right?

To be honest, I prefer amazon.com... it has a huge variety of the stuff I need and sometimes due to currency anomalies, I can get stuff cheaper.. than the local amazons..