- Scheduling is highly inflexible. When you say repeat monthly, it thinks you want it to repeat on the same day of every month... when in reality nothing ever works that way. What you really mean is you want it to repeat on the first Monday of every month or something like that.
- Highly inefficient code. I entered all my events in and it slows down to a crawl when pulling up the monthly calendar. When I looked into the code it was a total mess. It was making 31 separate sql queries (sometimes more) in order to build the calendar. Also, for repeating events, it cycles through EVERY SINGLE EVENT to see if there is a repetition that falls on the current day. It might be a good calendar if you had 4 or 5 events a month, but not if you have more than 20.
Stay away from this product, go with JEvents instead. So far I'm really satisfied with JEvents.
We have an efficiency build planned for JCal Pro. Those queries remain from the original standalone extcal. That said, I routinely use this for busy calendars and page-loads are fine. You might consider trying the speed on localhost or another server to test the speed.