I researched chassis dynos for about a year and a half. The very BEST chassis dyno for a turbo/supercharged car is the Superflow chassis dyno with dual eddy current AND water brake. There are only a handfull of shops with them. Inertia dynos CALCULATE horsepower. Water brake dynos MEASURE horsepower. (I'm being OVERLY simplistic here) Dynojet is the standard that most guys go by, though. It really depends on what you want to do with your dyno. My findings, after talking with many, many dyno operators across the country, is that alone they rarely make big money. They are a tool that lets you sell other services to make real money. A torque wrench really doesn't make you money,either, but you MUST have one to build an engine. IF most people in your area have a Dynojet (a FINE peice of equipment, mind you) and you purchase some other brand, then there will always be the ignorant masses that will go to the dyno that reads the highest. (Bragging rights) What is your intended use of the dyno? Are you using it in a full service performance shop, or are you looking into opening a dyno "only" shop? I'm sure Bill can give a better, real life testimony to the uses/profits of his dyno. For the money, I think that Dynojet is the best bang for the buck. When I was looking into purchasing one a few years ago, it would have cost me over $90,000 to get a Superflow Chassis dyno (with water brake and air starter option-so I could dyno sprint cars) up and running in the shop (in ground).