power brakes and check valves

[t300]

I just put in the Summit power brake kit into my 1970 c10. It came with a check valve for the included booster but I didn't have a hose to fit so just ripped the hose and booster off a 2002 silverado we had in the yard as it bolted up.

Out of curiosity I looked up the silverado checkvalve part number and it has a '7200lb power brake' spec. Some other valves have other weight rating spec.

So - what does this mean? is it just about max vacuum the valve can handle? Does it make a functional difference what you use? I'm not overly happy with the pedal feel and braking ability, fully realize you get what you pay for (mostly) and this kit was super cheap so I'm not complaining, but having said that I'm curious if checkvalves actually make a difference at all here.

thoughts?

ACDELCO 1791266 {#1791322, 18022219, 18029764} GM Original Equipment; Includes Valve & Grommet Info
7,200 lb Vacuum Power Brakes