Id considered something like this for my Insight. Any psi will make a seat of the pants feel increase. Hopefully the few psi that could be generated would not require preminum fuel either. Since I have a plug in kit, I could easily power it with that and use a switch under the gas peter for WOT operation only.
I had a supercharged tacoma with the trd supercharger. It can be driven when the super charges is not belted. Either way I got the same mpg. I got 18 mpg regardless of how I drove and 16 when towing a car. THis was basic driving, not FASing or anything beyond sidewall psi on the tires, sticking to roads with 45 mph and running 33 inch off road tires.
The other option is a chemical intercooler. I saw one on the power block a few weeks ago. I believe it was like 300 bucks, it could use windshield washer fluid and a qt of fluid would last for a few miles at a good spray pattern for some monster v8 engine.