Too many factors never make it easy. Are these from a rental fleet or the upper level demo end.
How much time have these skis seen. Are the bases in good shape or are they gouged or .... are they getting thin from ten too many times across the grinder? Are the edges still solidly affixed and no sign of repair along the base and edge?
I ski with Tyrolia demos on all of my skis .... they are fine! They weigh a few ounces more but they also give me the ability to do fore and aft adjustments. The toe can be moved fore and aft as can the heel, as such, I could find the "sweet spot" for my center of mass and balance ..... there is a mark on the ski and a mark on the boot for centering.
A cheaper demo will only allow you to slide the heel back or forward. So if your foot is larger and the heel is moved back, so the center of the boot also is moved back.
What kind of ski, binding and condition?