@Kira S (I wish cpanratings adds a feature to comment on a review):
Comparing WWW::Mechanize with Furl is not really apples-to-apples, since Furl does not support parsing/following links or form processing. As the Furl POD itself suggests, Furl is positioned as a faster alternative to LWP, not WWW::Mechanize.
After benchmarking all CPAN HTTP solutions and being a very long user of WWW::Mechanize; I ended up choosing Furl. Among 20+ contenders, it was among the top 5 in speed, and with a very low memory footprint. It was also the one who croaked the less over thousands of random urls.
Because it is lightweight compared to Mechanize, much more quicker, and it handle a lot of things automatically that Curl and others low levels HTTPer do not (Multiple Redirects detection hell anyone?).
Support with HTTP::CookieJar, nice simple interface, and just works. Documentation is a bit terse, but if you are familiar with LWP or Mechanize you should be fine. Used in production for external webscraping and as a Rest API call.
I tried this module for it's simplicity as a drop-in replacement for LWP::UserAgent. The API is very similar so I could just use it as a drop-in replacement for LWP.
Today, I used Furl for a small web scraping project - with quite disappointing results: Fetching ~ 50 URIs (non-parallel requests to a test server with quite deterministic response times) lasted ~ 30 seconds with Furl while LWP::Useragent did the same work in only 7 seconds.