Adding e-SATA Drive Changes Physical Disk 0 in Logical Disk Manager - Any Problem?

I am running Vista Ultimate 32-bit on a SCSI boot drive, which shows
correctly as Physical Disk 0 in Vista's Logical Disk Manager snap-in. It is
partitioned as Drive C. I have an additional SCSI drive for
data partitioned as Drive D that shows correctly as Physical Disk 1. The
SCSI drives are connected to an Adaptec 19160 host adapter in the PCI slot.
I recently added an external e-SATA hard drive to one of the internal
motherboard SATA ports configured as ACHI to allow for hot-plug capability.
Since apparently the motherboard SATA ports have priority
over those of an add-in HDD controller, Vista now sees my external e-SATA
drive as Physical Disk 0 and my SCSI boot drive became Physical Disk 1 and
so on. The logical drive letters of the SCSI drives
(C and D) did not change and I assigned the e-SATA as Drive letter H. Vista
seems to have adjusted to this situation and I have no problem booting and
using all the drives so far. In fact, if I unplug (or power off) the e-SATA
drive, Logical Disk Manager just shows no more Physical Disk 0. If I
re-connect the
e-SATA drive, it shows up as Physical Disk 0 again. I cannot beleive that
Vista is smart enough to adapt to this. I always thought that the boot
drive must be on Physical Disk 0, at least back in the XP days. My question
is am I asking for trouble by doing this and can I expect to see any
problems in the future by not having the boot drive as Physical Disk 0?
If I install an add-in e-SATA controller card, then the external SATA drive
becomes Physical Disk 2, but I'd prefer to use the SATA on the motherboard.
Does anyone foresee any problem with the boot drive
partition NOT being on Physical Disk 0? I'd appeciate knowledgeable
comments. Thanks.