I've used the demo for about a month, one problem I've come across as have other users is that it crashes or closes. It's a nice silent crash though you don't even notice it theres no crash dialog box it just shuts down without warming.

I have a few suggestions to make first of all use an icon instead of "MailHere" in the menu bar because space up there is very limited. Secondly allow the number of new messages to be displayed in the menu bar. Lastly I'm not sure if this is a bug but for some reason if I have mail open and mailhere open if I have new email it will appear in mail "inbox" but mail won't run my rules I have to manually run rules on new mail.