The Steel slaver has much better defenses than the Wind slaver, but is not as well armed. The weapon it has is mounted omnidirectionally, so it is harder to dodge. It's slow and big enough that a long range weapon such as a lancer cannon can be used against it effectively from far away. It is also slow enough to run away from, in the event that the player can't handle it.
Note: the Steel slaver has the “CyberDeck disarm” cyberattack, which can disable the player's weapons for a short time. It makes an EMP-type graphic on the player ship, but affects nothing other than the weapons.