upsides to making a portal to heaven  
   to   build  the   factory   there    
  
                                          
 first  of  all,  real estate: the highly 
 fractalized  geometry  (not  proven  but 
 likely to be the  case)  implies  almost 
 unlimited room; even if the portal  tech 
 would  be  stolen,  chances  of  running 
 into  a  competitor  is  close  to none, 
                                          
 secondly,  the  resources:  heavens  own 
 alchemical  properties   (proof  exist!) 
 makes  most base  materials  easily  and 
 readily  available.  once  the molecular 
 movement patterns are  mapped  out,  any 
 compound   can   be   created  virtually 
 without                            cost. 
                                          
                                          
  
   downsides  to making  a  portal to   
   heaven  to build the factory  there  
  
                                          
 current portal  tech takes  some  energy 
 to  hold open, which isn't a problem  in 
 itself.  test  results however has shown 
 that  without an active tether, heaven's 
 time flow breaks down  completely.  even 
 a  momentary  fluctuation  of the portal 
 would   render   all    remote    assets 
 practically  lost.  much  care  must  be 
 taken   to  maintain  portal  stability. 
 (one option could  be  several  portals)