The Slayer Helmet is slightly overrated, in my opinion. It gives you the bonuses of:
- [bleep]y Helmet
First of all, you don't even need a helmet to go to ToG, thanks to the 2 step skip. Second, who kills these anyways? They give good XP but have horrid drops, and come in low amounts.
- Nose Peg
No benefit, because Salve (E) has a higher bonus than Black Mask, and works on Aberrant Spectres. They do not stack, so the Salve E will take effect, and you might as well be wearing a normal nosepeg.
No benefit, for the same reason as Nose Peg. Also, the fact that unless you're going to the new slayer dungeon, Banshees have a whopping 22 HP, and the attack and strength bonus does very little.
The only real benefit IMO. However, most people kill dust devils either for charms or camping for Dragon Chains. The mask has no benefit when you're not slaying. Also, it doesn't benefit range... which is still a problem I'm amazed Jagex hasn't fixed. Why doesn't Black Mask give range a +15% boost?
I might still get it one day just so I can save space in bank while keeping all of these different items, but it's honestly not as good as it's hyped up to be...