they said the best parts were used for optimal performance and that upgrading will be a waste of $$$.I suspect it is more a case of "we used the best parts that would make the preamp sound quite good for the price, and we believe upgrading parts would not be consistent with our concept of a reasonable cost/benefit ratio that meets our price point."
One area I would be curious to hear about is whether any of you have upgraded the ($35) Alps motorized potentiometer to a higher quality discrete resistor volume control solution? The (poor tracking) Alps control is the single reason I have not previously purchased this preamp. I am not questioning that the preamp sounds good, but I suspect it would sound significantly better with a DACT, Goldpoint, or another type of discrete resistor volume control.