Looking at the options for a Purfi amp (VTV,Nord,Apollon) I see that they all offer their own custom input buffers. VTV seems to be the only one selling the kit that was shopped to the big manufacturers by Purifi originally, known as the "Eval-1".
I am kinda hung up on why would I not want what the designers shopped to the large equipment makers (NAD, etc), and why I should assume that the third party vendors are doing a better job on their input buffer implementations than the original designers of the Purifi system.
I know it gives them differentiation from other vendors, and there are already differences in quality of cases and it seems build quality. It allows them to charge more for their products, but will the difference be an improvement?
I would appreciate any information/opinions and personal experience you may have on this subject. Thanks.