Status_203 - 8:23 am on Apr 4, 2011 (gmt 0)
Thanks for all the suggestions. I'm going with Thunderbird/Virtual Identity though, seems to work as I need it to out of the box (and as an added bonus, on Ubuntu at least, is trivial to sync the calendar component with the multitude of Google calendars I need to track - never got around to working that out in Kontact).
Seems more responsive than Kontact/Kmail, and more stable. And it's synced all my mail locally, removing another worry.