I'm chiming in with those who have already described this as an especially handy and useful app. I don't routinely use even half of its features (it has so many!). But several that I do use regularly aren't easily accessible or even offered in some full-blown calendaring programs, let alone other menu bar type calendar utilities. And this program's implementation, and customization options, just make it a joy to use.
I'll also second the comments about the developer's responsiveness. I received a same-day response about a small bug I came across during my trial period last year, and the fix was in the next release put out shortly thereafter.
As for the price: I tend to judge a utility app's value by how much time and effort the app will save me over time, and the value of that time. After using this app for the trial period, I cheerfully paid $15 for it, with no doubt that it had *already* paid for itself. So have no thoughts that, OMG, I overpaid, now that the developer has dropped the price to $10. It's a bargain for what it offers.