Yeah, I agree. We'd have to know what % it is... And that is indeed the crux of the argument!
If it is incrementally (assuming one already wants the rest of the device, which is an assumption we are making) not a high % to add it to what exists as the rest of the machine, then all is good in the world just as it is right now :). If it is a high or medium % of the total price, then I suggest the things I suggest above, such as same product with no DAC and/or upgradeable DAC boards, etc. etc.
If it is incrementally (assuming one already wants the rest of the device, which is an assumption we are making) not a high % to add it to what exists as the rest of the machine, then all is good in the world just as it is right now :). If it is a high or medium % of the total price, then I suggest the things I suggest above, such as same product with no DAC and/or upgradeable DAC boards, etc. etc.

