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)