Pegasus Mail & Mercury

I wanted to migrate to M32 for IMAP support, but am finding *very* poor performance via IMAP.  I'm running on dedicated a 2.8gHz P4 w/ 2gb ram & SATA HD's , so it's not a hardware limitation by any means.  I've got a large mailbox (~10,000 messages) that takes forever to access.  I had to increase the TCPIP timeout from 30 secs ...