I only have a few hundred hours in HOI3, and most of those were restarting the same game because I had colossally messed up something; but, I loved the concept, especially the research and tech support and battle planning aspects. Those were/are superior with regard to choices, as well as having the look and feel of reality. Also, the slider bar domains gave me the power to do more research though at the expense of spying and officer training. HOI4 tech research is very streamlined (and good), but I'm always outpaced by time and end up lagging in gaining research in a number of critical areas. OTOH, HOI4's interface is much more manageable! In HOI3, I tired quickly of the incessant popups. Also, production in HOI4 is much simpler (and less confusing). I actually prefer the Battle planner of 4 better than 3; but I do miss the role of assigning officers and creating the mix of my stacks. OTOH, the point, click, and green check of HOI4 is extremely convenient. In summary, I think that they are both great games with HOI4 being easier to learn and play. Perhaps the final version of 3 is less frustrating in terms of AI; but 4 is pretty awesome and the devs keep improving and adding new content. Personally, I don't mind paying for quality, but I recognize that it's a perspective difference in each player's situation (so I'm not trying to start an argument over our perception differences).