I look for perfect url rewriting for good web ranking

[eluser]lenwood[/eluser]
The structure of your URL is pretty far down in the list of importance for search ranking factors. Page titles, header tags (h1, h2, etc) and the anchor text of your internal links are all MUCH more important. As long as the keywords you're targeting appear somewhere within the URL you'll be fine.

Suppose you want to rank well for the search term "denver pizza". All other things being equal,

Code:

example.com/colorado/restaurants/archive/pizza/24/denver/public

would get you to exactly the same search ranking as

Code:

example.com/denver/restaurants/pizza

Also, if you're doing URL routing you want to ensure that your server only responds to one version of the URL, otherwise you're opening up the possibility for duplicate content which will negate the value.