The Hendrix Sunn amp (JH 1200) is a pretty good (virtual) pedal platform. It's got
enormous headroom. You can smash it with fuzz up to the skies, and it sounds good.
I think the Satch VM model is actually pretty good for what it is modeling -- the model and the real amp are both very versatile -- but I'm going to be a bit heretical and confess that I just don't get
that excited by actual modern Marshalls (and I'm considering basically anything from the JCM 800 onwards "modern"
). I mean, they're all perfectly OK, and the AmpliTube models seems to generally do them justice ... I have not a single bad word to say about the AmpliTube "based on Marshall" models as models (except that I'd really like a "stock" early '70s Superlead model!) ... I just tend to use other things. If I want "vintage" and Marshall, I use the JH Gold, while if I want "modern", I tend to use models of amps other than the Marshally ones.
Basically the same with the Fenders: I feel like they model what they are intended to model very well, but I just don't use those tones that much.
I confess that I initially struggled with the German 34 -- and I had been really intrigued by the Bogner-based model -- but Jason Sadites has a good YouTube video on it, and I tried his presets for it (which variously use some of the different channels), and those work better for me. Using Sadites' presets as starting points helped me build some variations of my own. (I feel like the Ecstasy XTC 3534 is itself a bit "modern modded Marshally", and my ambivalence towards modern Marshalls may have affected my initial experience with the German 34!)
Weirdly, although I'm a huge Orange fan, I've somehow never quite gotten along with the OR50 model!
I probably need to reapproach it ....