Staub Frying Pan Convex On The Inside?

Hi Guys,

Got this 28cm Staub Frying Pan about 2 months ago. Cooked with it a few times, but I realized something:

1) Base is not completely flat, if I tap on the edge of the pan with some pressure, I can feel that it will lift the opposite end about 1-1.5mm (which is minimal). Or is this an acceptable tolerance. My Falk sits dead flat!

2) After heating the pan, I realized that the oil will run to the edges. Even when not heated, I use my fingers to run from the edge to the centre of the pan, I can feel a small gradual groove along the sidewalls. Seems like it was designed that way.

3) I am using a ceramic stove and I realized that the heat zone is not really even on the Staub pan. Certain areas of the pan will sear better than some. When I changed to my Falk copper pan on the same stove, I also see that the heat zone is similar to my Staub. The bottom of the copper will show the heat radiation marks. Hence, I was thinking is this the problem of my cheap ceramic stove.

So I am wondering, could my Staub uneven heat spread, convex pan surface and slight uneven bottom problems are caused by my ceramic stove? If it's not the stove, then could this just be a Staub or ECI typical design and material issues?

Hope to hear advises.