Comment by gabrielblack

I don't think so, this command could be significantly slow:

    cp myfile.iso /dev/sdb

compared with this one:

    dd if=myfile.iso of=/dev/sdb bs=32M

because implementation of cp have a fixed buffer, so if the amount of data is big and the disks fast, using cp you are calling more read() and write() syscalls than necessary, slowing down the copy process.