In a word - superb. Installation was so easy, and thus far it has functioned perfectly.
One small thing - my timezone was missing (Canada/Newfoundland, GMT -2.5). I added it to the preferences list and then had to modify func.inc to remove the (int) so that the half-hour timezone would save correctly in the preferences. I think there may be one or two other half-hour timezones out there....
One missing feature which I use a lot is 'Reply all'. I don't see it in the list of planned features (http://www.roundcube.net/?p=about). Maybe it could be considered?
Thanks again for this lovely webmail app.
Doug Robbins