There are lots of different formulations of brake pads and they do different things when they are bedded in. The R4's that we used to run would boil off binders when they got hot for the first time. This gas gets forced out between the pad and the rotor and you have no brakes while this is happening so you need to be ready for that. After that, the brakes work fine.

Some pads work by depositing a layer of material on the rotor, some don't. Some different pad compounds are compatible with other compounds, some are very much not. I bought my Stoptech kit used and my pads were incompatible with what the previous owner had used. After a bit of use, I picked up a nasty vibration that bounced the steering wheel out of my hands and made the car undrivable. I do not recommend bedding in with a different compound than you are planning on running.

Richard P.