Great report, Hans! Here's where my stock HX/DA differs:
The master volume on the stock model (as opposed to the modded 25th) is a continuous attenuator, not a stepped attenuator as you have. Thus I can dial "in between" the steps on your master volume, and find a good volume level for home use, recording, or other settings.
Sidebar notes:
I think when you play other guitars with the amp, you'll find this amp very revealing of the differences between pickups. Some amps are better at this than others, and the HX/DA is one of the best. In fact, I think it's on the level of a Two-Rock in being able to respond differently to different pickups and guitars. But the point is, you should have a lot of fun trying out your many guitars, and working with the pickups and the volume and tone controls.
The differences between the pickup sounds on my 3 guitars is truly night and day with the amp, you can really hear how they affect the tone. I've also found that the amp reveals the sound of the woods of the guitar very well. It makes picking the right guitar for a particular job extremely easy. There is no "Gee, I wonder what I should use to get this tone." You *know* what to pick up once you get an idea of the amp's response to each guitar.
Also, if you haven't tried this already, all the switches don't have to be HX or DA at the same time. I get various tones by switching the different ones in or out, and there is a lot of coolness to be had doing that.
For example, I can get some of the warmth and complexity of the DA setting by switching the first switch on the left to DA, and leaving the rest in HX. This gives me a "best of both worlds" setting that I like a lot with the SC58. Warm, with a little more grit than DA.
Finally, HX doesn't have to be set to flamethrower to get some very sweet overdrive; the gain controls are very responsive and there are a lot of very gritty-but-not-wild-man lower and medium gain settings to be had. I usually set my amp controls to produce a good crunch at 2/3 of HX gain, and a touch of DA gain, when the guitar volume is around 6-7.
Lower the guitar volume, and it's clean, raise the guitar volume, and the amp goes from a nice overdrive to higher gain territory depending on guitar volume.
In general, though, I think you have a good handle on what the amp does! Great job! It's pretty easy to dial in exactly what you want with it, isn't it?
Oh yeah, one more thing: Because the amp responds very well to nuanced playing, I'm finding new ways to approach picking and its singing tone is making me play more melodic parts, as opposed to "licks." That's an improvement in my playing, so the amp is really helping me make better playing choices.
I just love this thing. I played it all afternoon, and afterward, had a bite with a fellow studio owner, and all I wanted to do was talk about the darn amp. I probably bored him to the point where he decided to go ahead and schedule that hip replacement he needs, as a more enjoyable thing to do than listen to me.