An octane rating theoretically has nothing to do with an engines power production. Octane is simply a measurement of the engines ability to resist detonation. Every engine has an octane requirement. Using more octane could, again theoretically, hurt power. Geeks speak on gasoline.
http://www.faqs.org/faqs/autos/gasoline-fa...3/preamble.html

The point in the rev range where the engine is most susceptible to detonation is at peak torque (peak cylinder pressure). So the adage of using higher octane for protection in an extended high rpm situation isn't all together valid.

There is a difference between detonation and pre-ignition. And for the record there is no such thing as pre-detonation if you've ever heard the term thrown around. Check out this link for a clear description of each.
http://www.germanmotorcars.com/Detonation.htm

The engine run at extended high rpm is more likely to experience pre-ignition than detonation. Since the engine is obviously being loaded for an extended period and not being given the chance to cool there can be heat buildup. Spark plugs of the wrong heat range and casting flash on a piston or cylinder head can become heat risers that ignite the air fuel mixture before the ignition event. Octane won't help you in this situtation. Octane won't make the engine run cooler and it won't make more power. It will resist detonation and that's all.

Yes, most of the guys that run rotarys are using the cheapest swill they can find. It's a perk. With 9.7:1 compression there's no need for more octane. The rotary's inherit design makes compression ratios of over 10:1 yield no more power so there's never been that push for high compression ratios.

Having said all of that, I've heard anecdotal accounts of some "race" fuels producing more power simply because it's a hotter blend. Dyno time would be required to verify this and IMO a couple horsepower doesn't justify the expense and PITA to purchase fuel. Race fuels are usually devoid of detergents as well making them better to use when reading spark plugs if you're in to that sort of thing.

So Dan, if you're not getting knock on 94 stick with it. That's my .02 anyway.