It is the best equipment to get most of the time, easy and straightforward
Even outside of that, Culling Ritual is a great tool to get rid of common mana rocks, draw engines like Mystic Remora, as well as any other powerful cards that come into play quickly
That's all well and good, but if you can hang on to that Metalworker you often end up with eight, ten or even more mana by showing your opponent most or all of your hand
The best Shift target is probably Peter Pan - Never Landing but if you want to stick to Ruby cards, it would be the Peter Pan we just looked at, Peter Pan - Never Land Hero
Up to this point, outside of Blasphemous Act - which, lets be fair, never costs 9 mana - your options for cheap wipes in Rakdos were quite limited