Acronis 2010 Home - backup takes much much longer than Acronis 8

I am running a PC with XP SP3. With Acronis 8, a full backup (not sure if it was files or sectors but I think it was all files on the PC) onto my USB external hard drive took about 3 hours.

After running 20 minutes, Acronis Home 2010 says backup will take 13 hours more for backing up just my data files. On my PC the 160GB disk has only 100GB used for everything. The documents being backed up by Acronis are only 69GB (mostly photos and iTunes music).

Is 13 hours a reasonable time for this backup. If it is, I don't think I can use this program.

Thanks,
Jeff