Recently got the Core Prime and set up my email on it. There was no problem with setup.
The problems comes after.
1) If I delete email from the phone but not the server, the next sync brings that mail back in again. I don't want to delete the email from the server (keep for reference) but don't necessarily need to access that particular email on the phone.
2) I will read emails and keep them...the next sync will randomly mark read emails as unread.