First off just curious if anybody knows what values are currently being used for the trade 'cause I did a test and it took 44 T3 engies to take a T3 pgen from almost 0 to complete and on another test it took 16 SCU's to take a GC from almost 0 to complete. Another thing I noticed is that you can sacrifice for any building or unit (even those building in a factory) but you cant sacrifice for any kind of missile.
I feel like it should just be a mass for mass trade. Still wouldn't be used all that often IMO but could be useful in certain situations, also make it work on missiles.