Usually if you Google the topic with zr1.net afterwards you will find some good information here
http://www.zr1.net/forum/showthread.php?t=25970
Good luck with your decision.
If replacing an LT5 was the same cost as an LS I would be spraying also.
I chose to stay naturally aspired.
FWIW a friend of mine was racing a turbo BMW in the later 90s or such and had a nitrous backfire.
Blew the plenum through the hood of the ZR-1 and destroy the motor.