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)