I had ~30 mins with Stadium tonight and honestly it's impressive. The hardware is BEAUTIFUL. It's sleek and robust, tour worthy for sure.
@Digital Igloo you all should be proud.
I'm going to focus on initial impressions of Agoura here because its the feature I most care about. No disrespect meant to the other new features.
SO...
I played the Agoura SLO, BFDR, SFPR, Plexi, 800, SuperBass, Tweed Champ, Tweed Bassman, and the Revs. I hate saying this because its not helpful, but you'll get it once you play through it. We can argue about tones all day, agoura's feel and playing experience is light years ahead of Hx. There is more weight and solidity under the fingers. It's like you can feel the transformers. It feels solid like when I track my 2204 through the Suhr RL and a good IR.
There is more dynamic content, more and finer gradients to those dynamics, and it just feels like playing a nice piece of tube gear. I particularly enjoyed the volume knob cleanup on the marshalls and fenders. There are really pleasing overtones and lots of natural sustain, even when not using tons of gain. Straight up the SuperBass model might be the best feeling digital amp model I've ever played. Kudos to the L6 guys.
For the high gain folka, I only checked out the Revs...I'm sorry. There are definitely cool sounds in there but I was playing a telecaster with single coils. Im going to sweep back later with a LP with humbuckers and see what I can get out of the EVH and Bogner amps. I'll probably hit the Marshalls again too. This was a very exciting preview though.
In short - the feeling of playing through agoura is the win here...for me. This thing stays and I'm pumped for some eventual Mesa goodness.