I recently tried Win32::IE::Mechanize but it didn't work for me. In the docs it says:

The InternetExplorer automation object does not provide an interface to "popup windows" generated by security settings or JScript contained in the page.

The InternetExplorer automation object does not provide an interface to the content of frames from the toplevel document. This means that you need to load the frame explicitly (using the follow_link() method).

The basic authentication support is quite wonky and will only work with the get() method

Win32::IEAutomation has popup functions, accepts pretty much all js, works perfectly with frames, authentication is solid and is a lot simpler to use, IMO.

It might not offer as many possibilities as Win32::IE::Mechanize, but it fits my needs perfectly. Recommended to anyone (working on windows) who wants to grab pages containing js.