LOL, yeah, one of my neighbor friend gals is obsessed with everything Tweetie Bird. That typo just happened to remind me of her. Granted your owl doesn't look anything like Tweetie though.
I also found the eXtreme PSU calculator to be a bit too low in the suggested wattage, and it even has a cap aging factor. It also doesn't seem to give recommended amperage. Not the free version anyway.
I was wondering if it's associated with any of the guys running XtremeSystems forum, because a lot of members over there get by on as low wattage PSUs as they can, despite a lot of them acting like elitists.
Come to think of it, I've yet to see one PSU calculator that's worth a damn. IMO you're far better off just using a system power requirement chart for specific GPU setups, like this:
http://forum-en.msi.com/faq/article/power-requirements-for-graphics-cards