I don't think there is any intention to have the shim higher than the core by design, it's just very hard to mass produce a system like that with super low tolerances, at the cards cost level. The shims height in relation to the core probably varies from card to card and some may seem or actually be level, but unless measured with sophisticated equipment I guess you'd never be 100% sure.
I used a small new steel rule across the shim in a few places, while using the laser from my temp sensor I could see the light under the rule so knew there was a slight gap. This gap though was less that the thickness of one piece of standard weight printer paper. The printer paper measured 0.09mm with a quality micrometer.
gmat
Hopefully I have G-Force FX covered, I think you'll like it
......... all I need now is a card
