Audiosilente idler wheel versus Artisan Fidelity idler wheel for a Garraed 401


Greetings,
I am considering upgrading to a new idler wheel for my Garrard 401. Reviews on forums seem to agree that there is a noticeable improvement in sound achieved. There are two possibilities that I am considering. 

The Audiosilente idler wheel is US$365
Artisan Fidelity is approx. Euros 100.

I ma wondering if anyone has any commentary are experience which of these two may offer the greatest improvements. I am certainly interested in an improvement in dynamics and everything else that is possible!

Artisan Fidelity https://www.artisanfidelity.com/accessories/garrard-301-precision-idler-wheel

Material - Austenitic Stainless Steel CNC machined case hardened CNC ground inner coupling pin, near true zero measured radial run-out.  State-of-the-Art CNC/CAM Machining achieves ultra close tolerances and accurate concentric form. Heavy weight enhances flywheel effect.Periphery Outer Drive Material - Concentric, Molded Seamless Rubber based Composite, precision CNC ground, near zero measured axial run-out. Manufactured as direct OEM Garrard 301 Schedule I & II / Garrard 401 / Garrard 501 Model replacement part.

The Audiosilent is aluminum with a square rubber outside ring.
http://www.audiosilente.com/garrard-401-idler-wheel-garrard-401.html

Any commentary would be most welcome.
Thank you, 

mozartbrain
Mozart, There’s got to be more to that story. Machining down the diameter of the idler would reduce platter speed. That could be compensated by increasing drive speed but would hardly suffice to improve dynamics.
@dangcaonguyen 
@vetterone 
@lewm 
I think that the machinist who made the idler said that he had reduced the 'pressure' between the wheel and the platter. He found that this allowed more dynamics. I guess the platter was not so 'rigid' in its lateral spinning motion so that the needle moved with greater amplitude. 
Does that make sense to anyone or I am way off track myself?
Thx,

If the idler wheel is normally say 2" in diameter, and there is no allowance for the idler to move closer to the platter if it is reduced in diameter by say one millimeter, it will exert less force on the inner platter contact point.
What effect does that force have? Maybe additional damping causing a loss in information or conversely ringing making it appear there are better dynamics? Perhaps the additional pressure exerts an asymmetric force on the bearing and it’s reduction reduces the transmission of bearing noise.