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)