The Gulltoppr has been the absolute bane of my Falcon formations whenever I've tested it. I tend to rely on staying mobile and trying to quickly degrade a few key enemy units, but this thing just does not care about getting shot. I mean, sure, you can end up making it actually immobile, but you can't make it stop shooting you without devoting a serious beating to it, which lets all its friends off the hook. In addition, since it's staying still and often firing artillery cannons or Artemis V LRMs, it stands a good chance of hitting even very jumpy stuff. Have you seen what an LTC does to a Gyrfalcon? Crispy chicken nuggets with a generous helping of powdered glass.
Plus, between the +2 bonus and the ability to say, "yes, hmm, I think my Gulltoppr is gonna stay where it is, your turn to move," it can really screw up your initiative.
Whoever's running the Rhodes Project for the RAF could probably learn a thing or two.