I'm writing a sort of lit review and I'll post it as soon as I'm done. So far it doesn't really look like it would cause 'gh gut' or Cro-Magnon face etc.
(anyways... as far as i know, 'gh gut' is actually caused by insulin (whether it's your own or the injected insulin...)
It's still considered a research chem though and there'd have to be significantly more trials to know what the pegylated form could do in terms of adverse effects. the 'regular' mgf, whether its one of the synthesized forms or sth closer to the human endogenous mgf... i don't see how it would cause what you're worried about, it being a 'local repair factor' with very short activity.
The main receptor that is stimulated by IGF-1 on various tissues is simply IGF-1R. there are studies that 'knocked out' or blocked (don't remember which right now) that particular receptor in vitro of the tissue that was then exposed to MGF.... mgf still had the observed effects on protein synthesis etc. meaning that, while igf-1ec is a splice form of igf and igf can cause some bad sides... mgf does seem to have it's own unique mechanism, which does not include that particular receptor (the receptor that is associated with abnormal bone growth etc.)
and the distended stomach thing... it can be caused by gh BUT indirectly to my knowledge by stimulating igf-1 release by the liver. IGF-1 is good and important but if you inject GH or IGF-1 or slin past a certain point and for too long (or ur just **** outta luck) then it can cause some wierd stuff to happen because the three are part of an axis that can prevent cell death where it is necessary and can cause excess growth where it isnt...
and the bloated gut doesn't even necessarily have to be organ growth the way you're thinking... it can just be an enormous increase in visceral fat (i.e. ur got abs but ur still fat as ****! ****ing around with your bloodsugar/insulin/igf/gh too much can help u get a nice stubborn case of metabolic syndrome/insulin resistance et cetera. and that'll just make it even harder to get rid of the visceral fat. (more difficult than shedding the outside gut). another thing that can play a role is delayed emptying of the bowels. if u stuff ur face on a regular basis (overeat) AND you **** with your blood sugar.... ur intestines are gonna hate you. i.e. getting backed up i.e. gas bubbles that just hang out in the bends (u can see em on an xray tho). and at an extreme it'll obviously also just stretch out the linings/your stomach etc.... (i know the inside gut and digestion stuff first hand)
anyways (huge tangent..) i don't think u need to worry about the whole gh/insulin/igf-1 stuff..... if i were you, i'd be more worried about the peg version causing the heart to grow. lol... nah, i don't think so. no one really know at this point but since mgf is only released in musculature in response to damage i dont see why it would do that. u can test it out though... just do ****loads of peg-mgf for a few months and let me know what ur doc says. (**** ill pay you to do that)