I dont think so.
I use it all the time for backing up images to both DVDs and other hard drives or partitions thereof.
It splits the image into essentially equal size block in either mode.
I don't see any real disadvanatge in the splitting.
OTH, their compression is a little weak and I see no difference in their default setting of MED and the optional setting of HIGH.
In comparison to other app's which will compress my C: drive to fit on one DVD, Nero BackItUp uses 2 DVDs regardless of the compression setting.
I did something really stupid the other day and blew away my C: drive completely.
Fortunately, with the bootable DVD and the image on my other hard drive, I was able to do a complete restore.
Craig C: Comment on the compression (alliteration unintentional)?