safe to remove old kernels after installing latest mainline?

safe to remove old kernels after installing latest mainline?

I have installed the mainline kernel 3.10 as recommended here so that I
can have my wifi: http://askubuntu.com/a/322737/128334
I'm running into the same problems as why is dpkg configuration running
out of space on ubuntu 10.04 when there is space available?
Is it safe to run the recommended command in the blog in that answer? If
not, how should it be modified?
dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r |
sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^
]*\).*/\1/;/[0-9]/!d' |
xargs sudo apt-get -y purge