I had a query about a small issue with the component (caused by our SEF component, not by JCal), and this was quickly looked into and solved via the JCal support site.
Can't ask for better than that really.
However, there were one or two options that I required (flexible editing permissions, the ability for a single calendar to pull events from multiple categories) that were not included. Therefore I was not able to use it.
Customer support was speedy and polite, and I was offered a full refund.
Thank you for review.
Just for you information: Art Calendar is evolving component - we've added functionality to pull events from multiple categories and sections in version 1.1.0.
Mini-calendar module and other enhancements will be available in next release.