No, I am not saying that the Hero does not sync the sent items. I ma just used to when I reply to a message the icon changing to an envelope with a reply arrow on it. This is what I am referring too.
Also I have noticed that when you read an item on your Hero, Outlook does not display it as read.
This is very confusing over the weekend when I read like 50 emails and then come back to the office and they are not marked as read.