I finally made it to nanites!! Too bad I probably went through 1mil deut total and the upgrade will take 11 hours...
If you really do your math, you'll love NAT. I have level two NAT and my ship construction time is just simply amazing.
NAT level 2 + Shipyard level 9:
Large Cargos: Construction Time: 1m 26s
Probes: Construction Time: 7s
Destroyer: Construction Time: 13m 12s
Without two levels of NAT, Destroyer takes 53 minutes or so to build. Now I can build three Destroyers compared to just one.
NOTE: For each level of NAT, your construction time is cut down by half unlike Shipyard and Robotics where each level it goes down by a percentage. (50%, 44%, 40%, 37%, 35%, etc.)