There are a few different versions of the Fantom Facts Machine dyno, but as far as I have seen, they are functionally identical. (I had one of the oldest models, and I now have a brand new one).

The main drawback in my opinion is that the machine is hard-wired to run at 5.0v. This can be changed if you alter the circuitry, but the software that comes with the dyno is calibrated to calculate efficiency at 5.0v so it will throw it off.

It's a pretty good "middle of the road" solution if you are interested in motor tuning. It's a lot cheaper than getting a load dyno, and way more accurate than just using a no-load motor checker for tuning purposes. It's also still in production and readily available, which is also a huge bonus.

We use a heavily modified one (with custom software) in our shop for doing final graphing and plotting on our production runs, and it has been pretty stable and consistent. I find that the CE TurboDyno is a bit more versatile for rapid iteration and tuning, but they are also pretty hard to get these days.

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