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)