ko/s, time to format a cdrw

Hello,

I would like to know how many time does it take to format a cdrw with 
this command:

#cdrwtool -t12 -q -d /dev/hda

On my computer with this burn drive: samsung cdrw/dvd sm-352f, firmware T902
it takes more than 20 mn!!! (4X cdrw disc)

And always in "normal conditions", what is the speed of transfer data in 
kilooctet /second.
Mine is very poor...

Compare to windows softs like directcd or Nero incd, it is slower?

Thanks for your help.

Le gluon du net.