I'm assuming that you want a brake for watching trace, spotting misses and keeping on target in unstable positions? The current "go-to's" are the Insite Arms Heathen, PVA Jetblast and APA Little Bastard. Other good ones to look at: MDT's new hex brake, Khantrol Solutions, VG6 brakes and the Mad Scientist. I would stay away from the ebay/amazon brakes as they are generally nowhere near as effective/efficient, usually made of chinesium and will not give you the same results as the others mentioned above.