No disadvantages at all if your bios can be set to boot from HD0 if there is no bootable CD in the drive.
I have mine set up like this all the time - CD ROM - HD 0 - Floppy. It is also more practical in case you need to boot, for example, from the Norton System Works CD to find viruses, or from the Acronis True Image boot disc.
Win XP Pro SP1
Since the WinXP installation CD is bootable, and 'boot able floppy' consists of several disks and cannot be 'readily' created, are there any disadvantages in keeping the boot sequence at BIOS: CD ROM---HD---Floppy ? With XP at least, should the CD ROM be always the first boot device - e.g. for accessing the Console and perhaps the use of the KNOPPIX CD (great stuff!) ? Thanks.