Hmm kinda.
They do a lot of grunt work that regular guard troops would do and while there is the occasional super duper commando mission, with the exception of one or two characters they never feel really overpowered or invincible.
Over the course of series they take quite a pounding and from the original 3000,4000 or so soldiers there is not much left. It definitely felt more grounded in reality than most of the other stuff GW put out at that time. It's definitely the most " a soldier's life" kinda story i read from GW.
I also heard good things about the Ciaphas Cain series and the novel Cadian Blood, but have not read them myself.