If you browse thru older threads, there is a member @thieliste, which post I will quote, perhaps you may contact him, as it seems that he had both amps you are mentioning. Here is his post:
'My ex Gryphon Diablo 300 class A/B was outperformed by my present Vitus SIA-025 Mk2 class A and lately my Vitus was also outperformed by a Jadis DA88S KT120 tube class A integrated.
The Jadis is about the same price as the Diablo 300.
This is my experience in the past 2 years.'