Not actually bought safety critical, I leave those component choices to my local garage or specialist Indie.Ebay is a world of stolen, broken, fake, substandard rejects or all of the above.
Why anyone would want to buy safety critical components for a car there is a mystery.
The 'household name' items I was referring to were ignition components (that gives you a clue as to the brand) .. in the past it's been cooling system parts, oils, anti-freeze etc.