I have three different brand of brakes:
Answer: Very good fit and finish, works well on the recoil, the noise factor is the lowest of the three.
McMillen: Very good fit and finish, the least effective of the three, very hard to clean.
KDF Clone: VERY LOUD. Very effective, fit and finish are average.
A close friend has a Vais, the fit and finish are superb, noise level is high, also a very effective brake.
I have not had any effect the accuracy (other than I can shoot longer without a sore sholder).
Jim