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)