bru speed tweaking

I'm trying out the personal version of bru for backinging up some samab shares here. Just wondering who is using it out there an if you did any speed tweaks to increase the speed of backups. I did a test backup this morning of about 1 gig of data an it took 30 minutes to complete it. Based on that time frame the 11 gigs I have in the samba share would take up to 5 hours or so to finish. I did a test with the buffersize at 64k an 128k an it was same amount of time to do the backup in my testing. thanks for any help with this. I'm using a quantum DLT vS80 tape drive. thanks jack