Modo’s sculpt tools are bimodal which means they can work by moving polygons or by sculpting displacements, vector displacements, or bumps (in the form of maps) up to 4096x4096 pixels.
Using a straight ZB-like workflow, and a fairly recent GPU, you’ll get about a million on-screen polygons before it starts bogging down for me. The nice thing about sculpting on maps is that you can use vector displacements versus straight normal displacements like ZB’s alphas. This means that mapped sub-polygons don’t need to follow the base polygon’s normal in a straight line.
Overall, for a pure sculpting paradigm, it’s probably better than Silo (from my experience) but not as good as ZB. Where it shines is that it is very good if workflow from model to animation is important. Right now, there is a lot of work in prepping ZB models for animation, and it’s sort of a one-way process. Modo lets you easily move back and forth between your animation system and modeling to touch up models. (This is because you can paint directly on your displacements.)
I’m personally creating organics in ZB -> Modo -> Maya/C4D quite a bit for organic models, and using Modo quite a bit for hard body objects (like machines.) For simple stuff, like detailing an existing model and I’m in a hurry, I’m just going Modo -> C4D and saving steps.
ZB3 is a great original model creation tool, but it comes up lacking in hard body tools, workflow to other apps, and mac support.
(Yes, I know you can do hard bodies in ZB, it’s just more time consuming than other models because of lacking features like precision snapping, numeric rotations, bevel options, etc., etc.)
Overall, I can’t see removing ZB3 or Modo301 from my personal kit, but if I could have only one, I’d be using Modo because it’s far more versatile than ZB3–not better, just more adaptable to a wider range of tasks.
-K