I really like FireShot, simply due to the fact that it's reliable and it doesn't capture the annoying overflows that some webpages might have. As a frontend-dev I can snap a screenshot with FireShot and send it over to a friend without having to explain the "random white bars". I can only recommend this extension!
And this is only for the regular version. Maybe one day I'll have enough money to spend it on the Pro version to be amazed even more.
Keep up the good work, guys 'n girls!