The controls inside a model driven app have another look & feel compared with the controls inside canvas apps, but they could implement the same feature.
For instance in model driven apps, the controls have no border, and they become "active" only on "hover". In canvas apps, the controls have border from the beginning.
The code inside will be the same, but we need to be able at least to load another styles or use another classes. If the sdk would provide a property where we can tell in which app type the pcf is loaded, we can make the style change and maybe deal with more problems.