All I meant in my original post - in the context of a comment concerning periodic updates of products - is that the cynic in me would suggest that the differences between last year's and this year's version of the same amp often tend to be along the lines of 'slightly change the circuit topology so the front panel looks different and substitute a capacitor (or whatever other components) from X electronics manufacturer with a very similar capacitor from Y electronics manufacturer which we've negotiated a better deal on'.

The effect that meaningful capacitor changes may make is a different question and one that I personally know nothing about