I like MLCad for Space stuff and LeoCad for Technic stuff due to the piece selections.

Number of pieces?
pffff, the Cerberus (that's my BIG ship) is 108 studs long and has almost 900 pieces.

Let's see what sets I have used so far in the construction of this thing:
8459 Pneumatic Front-End Loader (582 pieces)
8462 Super Tow Truck (773 pieces)
8480 Space Shuttle (1366 pieces)
8485 Control Center II (1063 pieces)
8857 Street Chopper (457 pieces)
8865 Auto Chassis (898 pieces)
8868 Airtech Claw Rig (957 pieces)
8880 Super Car (1343 pieces)
(man I can't believe I have actually memorized those piece counts

)
I have not used up all of the pieces obviously, but six or seven other sets were also partially used to make the things, evening out the numbers. That unfortunately amounts to a lot of pieces.
