First, someone back in the review lists said they could never get their images to come up, no matter what they did. Initially I thought this was going to be the case for me as well. Turned out though that the general settings, hncaptcha v1.0 is set, and this simply didn't work (maybe that engine isn't installed by default, who knows, I didn't look into that). Changing that setting to the first choice, core v.1.1 made things work perfectly.
More disturbing to me was the fact that after the intial install, php errors were being generated on unsuccessful captcha entries and during configuration. Both of these situations were generating errors relating to mosConfig_lang being undefined, even though the joomla configuration file defines it. This required commenting out the if statements that checked to see if you had some other language choice set. A second error on an unsuccessful captcha related to another undefined variable, this one specific to this component, "securityImagesLet3rdpartyOverideChoosenPlugin" in SecurityImageChecker.php. I wasnt sure if that was a misspelling of "chosen", or some other error, but it was just a simple if condition commenting out that (and the first branch) got rid of this.
Now having said all that, I've been using joomla for all of a week and a half, and the install (other than being careful to back up the files that the patch required replacing and the other tedious elements like making sure ownership was a ppropriate on the replaced files and whatnot) still took less than an hour to get things up and functional. It's a component well worth having.