OK, Here is my results / opinions since I had both on my LT1

Power:
Supercharger, 648 RWHP / 612 Tq @ 12 lbs
Turbo, 643 / 649 Tq 11-12 lbs (Not completely tuned)

Ease of install:
Supercharger: a few hours ( or a weekend)
Turbo: A few years. (or a few months)

Cost:
Turbo cost more.

At the track:
Supercharger: Boost came on too violently, pulled good in the upper RPM's
Turbo: Boost came on hard but a little more gradually, Pulled like a beast in the upper RPM's

Trap Speed:
Supercharger: 137 mph
Turbo: 132 mph (In 108* weather) again not completely tuned and with a bad bog off the line.

Lag:
Supercharger: None
Front Mount Turbo: None.

Heat under Hood:
Supercharger: none to speak
Turbo: Is coated as the headders, Not real bad but noticeable more heat.

Change Boost:
Supercharger: PIA, Had to remove crank pulley, change to a smaller belt
Turbo: Flip of a switch or a spring change out.


As of now, I am liking the Turbo more, Yes it was a nightmare to install and I haven't driven it on the street yet, but at the shootout, to me after getting a final good tune in, I think it will be much better. At least no more belts to worry about (at $100.00 a pop) and if you want more or less boost for track or street conditions, like I said, just a button away..