Simple geek test is to use no models. but put a pole a couple of feet in front of a wall, offset slightly from camera lens axis. Look at the characteristic of the shadow and its edge, both with and without reflector. It will prove if it does anything at all to apparent size (I think you will not see a noticeable difference).
The next level of test is to stand a spouse or child as your model, and move the light a bit more off lens axis and higher, and see how the shadow of their nose on their face looks same/different.
From the above, you can decide if you wasted your money.
Here is a proof I did a long time ago, showing that a 5" x 7" softbox on a speedlight did little good to 'soften' shadow edges and modest good in decreasing shadow contrast, for a flash used as fill.
Left, no fill; center, native speedlight with no modifier; right, 5" x 7" softbox. Shadow edge (at red arrow) not visibly different!