Fancy mode, which is the best feature of this plugin in my opinion, requires all the years to be displayed in one row. Of course, the older the blog is, the more years you'll have. This is an unsustainable design. The blog I'm working on is seven years old, and therefore can't fit all the years on one row. The little arrow function becomes useless. Much of the css is difficult to edit or override due to !important tags everywhere. Overall, a bit of a pain to work with.
Otherwise, the rest of the plugin works well as long as you're not using fancy mode.