I&#x27;m not the best placed person to answer about Python, my background is primarily C++&#x2F;Java and functional languages. The types in general get out of the way. The ability to specialize behavior by types makes for some very interesting patterns and for a module writer add a huge amount of power. For the user of the module they rarely see the types.<p>The cons, top three from the top of my head, implicit array concat ( going in 0.5 ), String types ( going soon ), anonymous function performance ( gone by 1.0 )<p>None of these are show stoppers, but they do sometimes fall into the category of surprising. The core dev are very aware of the issues and if you look at the road map for 1.0 many are either well on their way to being fixed or are scheduled to be resolved.