D’Agostino Progression integrated vs Gryphon Diablo 300

The way to do it is to buy or borrow both and compare in your own system. Diablo is often available used, D'Agostino is not.
Most likely different people would choose one over the other even if liked both. I suppose, I myself would have a hard time if had to choose.
Diablo is Gryphon's best effort so far, Progression is not D'Agostino's best effort, that is Momentum integrated. Used Momentum could be the best option, if you can find one.

Sorry, but there's no way to make a statement on how good or bad the amps are without owning both amps. I see that happening a lot on this forum. I own the Gryphon Diablo 300 and its a great integrated amp which retails for ~$16k, Dan's Momem\ntum retails for about three times more, also a factor to consider.

Yup.  Stupid thread.

Stupid DUDE!!

have not heard the Gryphon, but I heard the Momentum and then was able to find one used. It ended my search for the sound I was looking for. "mike drop".