Q: Lowering brackets or threaded lowering links, which is better for a Model S?

Brackets are the more foolproof choice here. Generic threaded links require dialing in each corner and invite installation error, while these preset brackets drop every factory setting one predictable step and need no permanent modification to the car. This kit specifically does not swap your links for generic threaded ones. If you want fully adjustable, mechanical ride height instead, that is the territory of a race coilover, not a bracket.