Space hulk in its simplest form, without lots of tweaks is fine.
Probably doesn't help you, but i'll be writing my own set for an Aliens vs Marines vs Predator type game - similar fastplay to my AR:SE zombie rules - time scale for a working draft, realistically isn't for 4-6 months, but i'd always recommend writing your own, compared to buying something based upon other people's ideas/preconceptions.