hmm. just my personal opinion that their squishy and easily killed. personally i use them as sacricies. i send em against human knights. then ignite the area (fire) and burm them both alive.
"Orks is never beaten in battle, if we wins we wins, if we die we die so it don't count as beat, an' if we runs for it we don't die neither, so we can always come back for another go!"