I've had both StopTech and Brembo on my car. I only have anecdotal experience with AP, so I will refrain from discussing it.
I think StopTech definitely offers the
best value. Its bridge design is excellent for pad changes, but it could also be an issue if the fitment is not 100%. I've worked on cars where the bridge required some slight modifications. There are also other minor fitment issues I've experienced on StopTech, but StopTech in all cases responded and resolved these issues in a timely manner.
From my chat with a StopTech executive, they have been bringing in-house a lot of manufacturing processes that were previously outsourced. I think this is probably the source of some of their "hiccups."
My StopTech kit was on the track extensively and it held up extremely well. It also found a great new owner
Brembo, IMO, offers the
best quality. In each Brembo box you will find a checklist where a human being physically verified that all the parts are correct based on the part numbers and present before shipment. I never saw this type of list from StopTech.
Operating cost... Brembo has always told me that their rotor, which costs more than StopTech, will last longer than StopTech. Unfortunately I don't have the time nor resources to verify this claim.
Pads... StopTech certainly has a wider (and cheaper) selection of brake pads. Brembo's aftermarket pads are more limited and more expensive (due to larger size and less production volume). Besides, what else do you need besides Pagid Yellows
