Castellon, there is nothing weird about having a multi boot, even with identical OS versions. For example, the home PC's of several employees of one of our customers have this with Win2K. One is used for business, while they work at home, and one for private use.
What IS a little weird, is the reliance on Microsoft's multi boot. That doesn't do a good job of separating the OS boot partitions. A better solution would be something like BootMagic from PowerQuest. That really separates the OS's to the point that one partition hides the other, so viral infections cannot spread from one boot to the other, or applications mess around with the wrong registry files, program files folder or start menu.
I personally have 3 separate C partitions, and a logical D with OS/2 Warp 4 installed on it, all managed by BootMagic.
Jan Peter