Walk into any UK parts factor and you'll be offered three tiers: genuine manufacturer, OEM-equivalent (the firm that makes the part for the carmaker but sells it under their own brand), and budget aftermarket. Here's what actually changes between them.
Genuine (Ford, VW, BMW etc)
Same part as fitted at the factory, in a branded box, at a 40-80% premium. Worth it if your car is under warranty or you're chasing absolute factory ride quality. For everyone else, it's mostly the box you're paying for.
OEM-equivalent (KYB, Sachs, Monroe OE-Spectrum, Bilstein B4)
These are the firms that build the original parts for the car manufacturers. Same engineering, same tolerances, different branding. For most UK drivers this is the sweet spot — factory-grade ride for roughly half the price of a genuine part.
Performance / uprated (Bilstein B6/B8, KW, Eibach)
Firmer damping, sometimes shorter springs. Great for ST, GTI, M-Sport and track day cars; overkill on a 1.0 hatchback that just needs to pass an MOT.
Budget aftermarket
Unbranded or cheap-brand dampers from generic sellers. They'll bolt on, they'll pass an MOT next week, and they'll usually be tired again inside 18 months. False economy on anything you keep more than a year.
Our pick for UK family cars
OEM-equivalent (KYB / Sachs / Monroe OE-Spectrum), pre-assembled with the spring, top mount and bearing. That's exactly what we build at StrutMate UK — factory-grade parts, mechanic torqued, ready to bolt straight on.