Compare how both get Torchwood out of the way when they might otherwise ask awkward questions:
The Master - sends them to the Himalayas on a wild goose chase.
HM Govt. - blows up their HQ and sends assassins after them.
Of course nobody's perfect, and the Master does occasionally terminate employees who have outlived their usefulness or get on his nerves - e.g. Chan-To, though in that case it wasn't actually The Master who originally hired her, but his predecessor Yana.
Any thoughts?