Mulberry is the most well-behaved of the applications I have been able to use. It does have some bugs, however, and a particular annoyance around it's use of non-standard names for time zones. Mulberry is the only client I have used so far which can issue a MKCALENDAR command or which will display a hierarchy of calendars from a single configured URL, dicovering the calendars through recursive PROPFIND requests.
Note that Mulberry has a complex user interface. When I wrote this I went back into Mulberry and initially thought that DAViCal had regressed somewhat and that these instructions didn't exactly work... :-) It turned out that these instructions worked just fine when I followed them to the letter the next day. Go figure. I think I need to record some screenshots of this one...
If you're using Mulberry on Linux you probably have really crappy fonts purporting to be Helvetica, Times and Courier - go into File -> Preferences -> Fonts and change them to something nicer as soon as possible. Apple paid a lot of money to license those fonts, but few Linux users or distributors do.