PAD (Portable Application Description) files for shareware / freeware

I've been told that I should include PAD files with the freeware applications I distribute so hosting sites can list the information correctly and check for updates, etc.

Can you give me some info on using PAD files? Here are general questions which come to mind:

Is it worth the effort?
Do you use PADGen or an online tool like www.padbuilder.com?
Do you digitally sign yours?

Solution

I do use padgen, it does not take too long to make a pad file, but what takes time is submitting it... just copy+paste stuff from your marketing material into it.

keep storing all your pad files on your webserver and new version updates are listed in 1000+ small shareware/software sites automatically. however, download amounts from these sites are usually < 1000/mo.

not signed mine.