Looks near identical to one I got from NAPA the past Spring. Mine works very well. Mind you, I still check the fluid level in the radiator top tank to insure its at the level specified in the FSM:1.25" below the filler neck seat. I've found that more than this doesn't permit enough room in the tank for proper cooling, and sure enough, the temperature can go up 10 degrees or more.
With the right coolant level, I get a presence of just a few table spoons in that overflow tank when the engine is cool. But when parking briefly after running in hot traffic, it does catch a bit, which then gets sucked back into the radiator as the coolant contracts. My system maintains excellent equilibrium.
Put the tank next to the radiator, with the cap at the same height as the radiator cap, run the overflow to the bottom of the tank, and all should be well.