It depends on what you want to do with it and how large ur budget is. It also tends to be a bit of a matter of taste. Myself I use 3dsmax and I'm loving it, but it's also quite an investment if you dont intend to use it professoinally.

C4D is a popular app for people who want to continue to a program that has good modelling tools and advanced render and material options. Another pro for C4D is that u can purchase it in modules, which means you dont have to spend THAT much extra money in one go and could collect the modules over time, or ofcourse simply leave out those u dont use.

Lightwave i've heard has an easy modelling workflow. But i found it quite a lot more difficult to get to grips with it then with 3dsmax.

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