I love my Waterfox 64bit! Been using it for a while now. All my extensions work. If you happen to be a user of Roboform, they don’t offer a 64bit plug-in for Firefox/Waterfox. But LastPass works perfectly as a Roboform replacement. Speed is the name of the game and once you go Waterfox 64bit, you’ll never look back!
Be sure to read the Waterfox FAQ:
http://waterfoxproj.sourceforge.net/faq
Join in the Waterfox forum:
http://www.overclock.net/t/975626/waterfox-9-0-dec-20-2011-firefox-64-bit
LastPass plug-in download:
https://lastpass.com/misc_download.php?noscroll=1&tab=windows&anchor=ff#windowsff
LastPass user manual:
http://helpdesk.lastpass.com/