Access 2007 definitely has performance & stability issues in several areas.

Example: The user previews an Access report on-screen, and then sends it to Word in RTF format. With Office 2003 on an old Pentium 4, it took about 15 seconds. After upgrading to a new Xeon and Office 2007, the user waited for two hours before Ctl-Alt-Delete to kill the process. Solution: uninstall 2007 and install 2003. Problem solved.

At one customer mixing 2003 and 2007, 2007 would occasionally insert non-English characters into records.

At another customer mixing 2003 and 2007, Access 2007 corrupted the file (Unrecognized database format) that could not be repaired using either 2003 or 2007.