Here are a couple links for your reading:
New To Us 2007 Monarch 33SFS
The "rusty slide seal" problem was covered in a number of other iRV2 threads, several posted by the iRV2 user formerly called "Monaco Mama." She has some pictures posted on this Web site. The problem may not apply to the 2008 HR Admiral/Monaco Monarch.
Our 2008 has the smaller (than the SFS) slide on the driver's side and a bed-only slide on the passenger side. We haven't had it long, but I've gone over it enough in the past two months to be happy with our choice. If you have any specific questions, ask away.