Hard question
Longevity has a lot of variables. How you treat your equipment, what filth you have to deal with, if you use hot water and chems, all of these things will effect how long the equipment stays in good working shape. SS QC's are much more chem resistant than brass. Use brass for cold water, but SS will hold up to hot better. Also think of usng viton O-rings when using hot water or chems. They really make a difference in the preformance of a socket. Manufactures can make a difference also. Hansen is a band recognised by the pros as a quality QC,yet the price keeps many from using them. Other manufactuers QC's have different features that can be important for some, but usually if they are purchased on price, the old saying "you get what you pay for" applies. There are things you can do to prolong the life of some QC's. File down a plugs rough areas so it will slip into the socket easier. File the end also so rough areas do not cut o-rings in the socket. Do NOT lube sockets with petrolium oils. They can cause the orings to swell or even get soft. So treat your equipment like you want it to keep performing everyday. Change worn equipment to make your days Briter! Use an o-ring that will stand up to the type work you are doing. And let me know of any ways I can assist you.