> Anyone here use this testing in the wild? Where's it most useful? Do you have the issue I described? Is there an easy way to overcome it?

One example would be when you have a naive implementation of some algorithm and you want to introduce a second one, optimized but with much more complex implementation. Then this naive one will act as a model for comparisons.

Another case that comes to mind is when you have rather simple properties to test (like: does it finish without a crash, within a given time?, does not cross some boundaries on the output?), and want to easily run over a sensible set of varying inputs.