how to configure going direct for 50 sites

We use two machines as parents and two machines as siblings. I want to
use these machines to get pages except for pages from about 50 sites for
which I want to go direct to the site. In the examples below, rather than
give these 50 sites, I'll just use two sites called direct1.com and
direct2.com.

There seems to be four methods of doing this. Can you please tell me
which is best. Thanks.

Method One
   Although the Squid documentation for local_domain seems to imply that
   the machine is 'local', this seems to be the easiest method to use.
   I just need to include the one line:
      local_domain direct1.com direct2.com
Method Two
   Or you could use cache_host_domain. However, the difficulty with using
   cache_host_domain is that you need to do it for each of the neighbours:
      cache_host_domain parent1.ac.uk !direct1.com !direct2.com
      cache_host_domain parent2.ac.uk !direct1.com !direct2.com
      cache_host_domain sibling1.ac.uk !direct1.com !direct2.com
      cache_host_domain sibling2.ac.uk !direct1.com !direct2.com
Method Three
   Or using a hierarchy_stoplist only requries one line:
      hierarchy_stoplist http://direct1.com http://direct2.com
Method Four
   Most of our users use browsers that can be configured to
   use an "auto proxy configuration file". So the JavaScript for
   this could be written to go DIRECT for all of the 50 sites.

I guess that Method One is best.

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