Nice.

Model numbers and/or prices? Where did you get them?

Does the spring loaded mechanism and/or the flexibility of the tank (doesn't look too flexible) affect pressures? I was picturing the 75 pound water input causing a slower start at a faucet until that slack was absorbed, then having excess pressure wanting to push out as you shut the water off . . . But that's all in my head!

Also, when this is actually used as designed for a sprinkler system, to gravity feed it, doesn't it have to be ABOVE the sprinkler heads? Are YOU setting up for gravity feed? How?