An important question regarding 301 redirects

[RoniShwartz]

Hi folks, I have a slightly complicated issue I hope you can help me with...

I have a three years old website, with thousands of indexed pages and PR-4

For branding purposes, I want to "mask" sections of my website with different domain-names, and add a 301 redirects to send viewers to the relevant pages...

Here's what I mean: Let's say I have a website about ethnic foods from around the world, called worldethnicfoods.com and the URL of the section about China is worldethnicfoods.com/China (with sub-sections, like worldethnicfoods.com/China/Cantonese and so on...)

Now, I want to re-name my "China section" and give it the domain-name : chinabestfood.com (which will re-direct viewers to worldethnicfoods.com/China )

My questions are :

1. Am I going to complicate matters by doing so ?
2. Is the new, keyword-rich, domain name going to extract some 'SEO juice' for me, or what matters is only the actual URL, not the 'mask' ?
3. in terms of SEO : Is it wiser to designate a section of the website as a seperate website (and, hence, the enjoy the reputation which the site already has with Google), or should I just create a fresh website for this specific section/s ?

Your expert advice is really, really, needed (and appreciated, of course... )

Cheers, Roni