I am running the final RC version of ESS and I'm very disappointed in the effectiveness of its antispam module with both of my email clients! My email clients are Outlook 2007 on my desktop and Outlook Express on my laptop. While ESS' antispam is working, it doesn't seem to 'learn' what is or isn't spam as I repeatedly get email from the same spammers... I 'tell' ESS an email is spam by clicking on the Spam button and it then moves the email to my junk folder, but within a few days I receive more email from the same spammer in my inbox! Unless this poor antispam functionality has been improved in the newly released version, I would hesitate to buy it.