Does JSBSim have issues with small planes?

[alphamikeuniform]

In another forum someone mentioned that "JSBsim has issues with small planes" (small planes = rc model aircrafts).
Is this a known limitation of JSBSim?
In my understanding, JSBSim is just a (albeit fancy) 6-DOF rigid body motion solver, and it should be perfectly fine to model motion of objects with the size and mass of rc model aircrafts.
I read somewhere that very small masses can yield instabilities in motion solvers. But the categorie of rc models doesn't count as very small mass, or does it?