I did a comparison last night with the models on the DT25 in standalone, versus the models in the HD500.
With the Park 75 Pre (not the full model with power-amp sim) , the HD500 just doesn't have the same amount of gain as the DT25 in standalone. Even with the drive cranked, it just doesn't have that ooomph.
So I changed the amp to the full version and - wow - that's more like it.
When I originally set up the Park and Marshalls, I used the Pre versions in the HD500. And they just didn't have enough of that Marshall gain. Even with the drive maxxed, I still had to add a tube screamer block in front to get enough gain, especially for leads versus rhythm sounds.
I'm not talking about a ton of gain. I had tried to get a "Jimmy Page Heartbreaker" tone using the Plexi Lead 100 Pre with the drive at 100% and still needed a Tube Screamer to get close. But I switched to the full model, and I was able to back the drive down and POW! there is is. I had the master volume on DT25 at about 75% and the channel volume pretty low.
I know it is documented that the voicing of the models in DT25 are based on the Pre versions in the HD500, but after making this comparison, I'm not so sure!
I will probably leave my clean amp presets alone. But I think all of the Marshalls sound so much better using the full versions in the HD500. The JTM45 full is pure AC/DC crunch and I never got that out of the Pre voicing.