Super Heavy vehicles also function much more effectively than normal ones do. For example, they can move at Combat Speed, and still be able to shoot all of their weapons, which can all be separate targets, should the shooter choose to do so. Also, when they explode, there is a chance that the blast radius extends further than the normal 1d6, and be as strong as a Str 9 AP 2 hit.
Gargantuan creatures are just bigger Monstrous Creatures who have higher stats all around, and are immune to Instant Death effects. I think they also roll an additional 1d6 for Armor Penetration, but I'm not sure.
It is also worth noting that neither of the two are affected by Psychic Powers of any kind that do not have a Str Value listed with the power.
I thought about posting something like this when you asked that question last night, Chase, but was way too tired to think clearly enough to put something this coherent together. Hope this helps!
