3DS Max is certainly easier to jump into. As mentioned already the UI is more consistent with your typical modeling software, whereas ZBrush is very unusual and takes time and practice to get down. Also, subdivision modeling in general is easier to master because it is more absolute, and less abstract. It is easier to maintain your geometry as well because you typically don’t work with a very high number of polygons in subdivision modeling software. Zbrush as a sculpting program was optimized to handle hundreds of thousands (or even millions if your rig can handle it) of polygons in a modeling session. This is why Zbrush is great for character design. With the wide number of brushes available, you have more control over the polygons and the level of detail you can add. However I will say that Zbrush 4R7 seems to do a much a better job of handling subdivision modeling with the new modeling tools they added. It is also MUCH cheaper than Autodesk software. It could offer you the best of both worlds for a better price. Than again, that really depends on your creative needs. To recap though, 3DS Max is much easier to get into. You might even consider starting there before using Zbrush.