wilwood makes some very good brakes, no question. and at about $700 the system you linked to is certainly affordable, since the factory KH system runs from about $600-800 depending on where you buy them from.
the thing you have t consider though is, how available are the parts? will you be able to get what you need in case of failure in places like resume speed iowa, or moosebreath montana?
or even in your local parts store? when you walk in and tell the parts clerk your system is a wilwood system for a 69 mustang, will they be able to find the parts in the store computer? or will he say we dont sell wilwood parts? or will they ask what is wilwood?
on the other hand, if you walk into said parts store, and tell the clerk you need pads and rotors for a 66 mustang, they can handle that, so can rock auto. note i said 66 mustang because in 69 the factory went to a single piston caliper, and the KH system is the earlier four piston design.
the other thing you can do, if you are on a budget, is get the NPD mustang catalog and piece the system together from their catalog as they have all the parts individually. it will take more time though.
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