One thing about supercharging and turbocharging - they both add compexity which is a liability because now there are more things to break and malfunction. (However, beware of high accelerations of trick NA cams. More load on the valve train and hence higher propability of failure.)
If you go by the 650 HP limit most people assign to the bottom end, then a NA 650 HP would be the most desirable due to the simplicity issue.
For a given level of torque, forced induction actually provides a "boost cushion" for the piston during overlap. This reduces the max tensile load on the rod bolts. This is always a good thing to do. So this is an advantage.
The real issue is probably finding someone who can build a 650 rwhp NA engine. To do this, they will have to have their bag of tricks in order. A lot of people simply do not know how to do this.
On the other hand, a supercharger merely needs a good fuel and spark management system with the right compression ratio to get the 650 rwhp.
At 650, you don't have to get into genuine supercharger cams which are proprietary. Nor will you require proprietary technology regarding wet flow, swirl/tumble, combustion chamber design and the like to get the 650 NA.
Keep in mind that when they needed more HP for WWII fighters, they added superchargers. Same thing with trucks, turbos. The brute force method. No need for trick technology.
One other thing, drag racing -v- track racing:
Every time you hear someone talking about HP in a Viper, the next thing discussed is 1/4 mile results. Well, what works for drag racing will not work for road racing. One local 50 lap asphault main event would wear out or break a drag racing engine. Heat gets into everything. Oil starvation during cornering and braking. Continuous operation at high rpm. And of course, brakes run orange.
Anyhow, that's the way I see it...
Tom
