Question on RAID 1

I have a Dell 2950 with hot swap drives. I have 2 physical disks with RAID 1 configuration and have installed the OS and exchange 2007 on this virtual disk. I want to test if, let’s say I shutdown the server and pull out the 2 physical disks and then replace them with another 2 physical disks and then power up the server again. So of course there will be no data on the new disks so let’s say I install the OS and exchange again, but for some reason I want the old disks back. Can I just shutdown the server again, pull out the new disks and then replace them again with the old disks, then power up the server, will I get the exact old system back or will the server wipe the old disks?
Is this confusing? Hope it’s not!