Earlier quoted context omitted.
I use the Google Apps/Gmail interface also. I've found that as it has matured over time there are less reasons I would want a desktop client and more reasons for having the portability of a cross platform, location independent web interface. Gmail is a class act when it comes to web apps.
I use IMAP on gmail with opera. I need a desktop client, for times when i'm not connected and quickly need to search an old email for some small little detail. I just use it as an offline backup, and keep it synced.
All my mail is synced locally but I can still use the Gmail interface.