The turbo fan is there to look nice and act as a support for the one way bearing. The reason there is a performance hike is because you have got rid of a massive air leak where the hex shaft goes in. Just be careful not to go too lean as these cranks will shear the pins off due to the loss of support from the turbofan.

I'd get that LC 2002 and make my own box. The other 2 are fine but less powerfull. Definately 12V. It's cheaper.