surely they have the wrong value estimate and vehicle definition for the Aprilia.
Never seen an Aprilia with this SU mod but I did this for a ford 100e sidevalve and got about 20% increase in power compared to the Zenith...
I have never seen that mod either, but the VSCC would probably not like it being such a modern SU. I'll bet it improves the performance though. I'll also bet it fetches rather more than the estimate!
Regards, John