If you use 10-20ius's of humalin-r or humalog Pre or Post workout, you'll end up retaining on average an extra 10-12lb above your normal weight. You'll look fuller, feel SUPER PUMPED in and outside the gym.
If you control for calories, you can have the best of both worlds. Gh allows you to run silly amounts of slin and have it work favourably without causing too much fat gain.
but, my general advice is, if you're natty, just don't bother running shit like slin or gh solo, not worth it.