All these AJAX mail systems work fine for a while, then they start slowing down. Is it the amount of mail in the mailbox? The number of folders? Or is there a security flaw in AJAX related to mail systems?
Every time I use an AJAX mail system - even this latest one where I imported all my old mail - the system goes quickly for a while at first and then after a while suddenly the performance becomes a dog. Maybe it is the amount of mail in my mailbox of something but it seems to be something more than that.
I have nailed down in the case of my current webmail system that it is probably not the network - unless someone is hacking all four different networks I use at different times.