I have no answer on your cheap throttle body question, but I do have a question on increasing throttle body size.

What are the gains from increasing throttle body size?

Horsepower, torque, throttle response?

The 2010 Challenger SRT I just got has an Arrington 85mm throttle body on it.
It was done at the same time as a Comp Cam kit, Kooks headers and hi-flow cats