Too many problems at the moment Rated 2 out of 5 stars
I've partly given up on installing themes with the One Click Add-On, because at the moment it is too screwed up. It installs themes inside the Plugins-folder all the time. The permission of the files has to be manually changed whenever I want to change a file inside the folder that can't be changed from within the admin panel of WP. And if the theme doesn't show up at all I've got more work to do than I have when I install it the tradional way from the start.
But for installing Plugins it's mostly alright.