I think there is another dimension to this argument.
I have found that, within most equipment lines, there is a price point optimum - above it, the differences are smaller, below it the magic is compromised. I can always tell when I get there during auditions. I suddenly stop listening to the sound and start listening to the music. I often have to snap myself back and remember what I am there to do.
The disadvantage of the approach you are taking is that you may settle below the optimum point for preamp while buying incremental improvement in the amp
I have found that, within most equipment lines, there is a price point optimum - above it, the differences are smaller, below it the magic is compromised. I can always tell when I get there during auditions. I suddenly stop listening to the sound and start listening to the music. I often have to snap myself back and remember what I am there to do.
The disadvantage of the approach you are taking is that you may settle below the optimum point for preamp while buying incremental improvement in the amp