Backup Exec Information Store vs Shadow Copy Information Store

What is the best and fastest way to backup the Information Store for Exchange 2003 on a Server 2003 using Backup Exec 9.1, for both backup timing and different recovery options.

Should it be done using the main selection of: Microsoft Information Store > First Storage Group
OR
Shadow Copy Component > User Data > Exchange Server > Microsoft Exchange Server > Microsoft Information Store > NTS02 (server name).

>>>

When running a backup job for our exchange server 2003 sp1 using Backup Exec 9.1 sp2, and
setting the selections to include the Microsoft Information Store > First Storage Group, as a normal selection, in addition to including it as a Shadow Copy Component > User Data > Exchange Server > Microsoft Exchange Server > Microsoft Information Store > NTS02, it causes the following error to occur in the backup log:

>>>Backup Set Detail Information
Error, Unable to open \ because it is currently being backed up by another process.
WARNING: "\\NTS02\Microsoft Information Store\First Storage Group\Mailbox Store (NTS02)" is a corrupt file.
This file cannot verify.
Database or database element is corrupt
Error, Unable to open \ because it is currently being backed up by another process.
WARNING: "\\NTS02\Microsoft Information Store\First Storage Group\Public Folder Store (NTS02)" is a corrupt file.
This file cannot verify.
Database or database element is corrupt
Log Files
Error, Unable to open \ because it is currently being backed up by another process.
WARNING: "\\NTS02\Microsoft Information Store\First Storage Group\Log files" is a corrupt file.
This file cannot verify.
Database or database element is corrupt

It does not give this error when using the default selection criteria from the main selection list, but does take 2-3 times longer to backup.

Here is some of the timing information known so far...

Job server: NTS02
Job name: aBTD NTS02 >>> Backup-to-Disk
Job started: Friday, April 15, 2005 at 4:00:04 PM
Set Information - Shadow?Copy?Components Shadow?Copy?Components
Backup Set Summary
Backed up 8 Shadow Copy Writer(s)
Backed up 8 Shadow Copy Component(s)
Processed 13,845,578,350 bytes in  25 minutes and  11 seconds.
Throughput rate: 524 MB/min

>>>OR

Job server: NTS02
Job name: aNTS02 Full >>> DDS4 TAPE
Job started: Monday, April 11, 2005 at 4:00:11 PM
Set Information - \\NTS02\Microsoft Information Store\First Storage Group
Backup Set Summary
Backed up 2 Exchange Server store(s)
Backed up 0 Exchange Server log(s)
Processed 12,674,180,278 bytes in  1 hour,  9 minutes, and  5 seconds.
Throughput rate: 175 MB/min