I`m tempted to say the Gleichauf fan is much better than the first fan ever, the original Byron.

Both are tractor fans, but Byron hasn`t the pitch to match top speed. Thrust at static yes, but not speed..

I`ve had them both, one the very same model, the same engine, and there is no doubt at all.
If you can install a Ramtec, this will get you as far as you can get in DF, as long as the engine is top match.

As they say, cents bla bla..

G