PIM Systems

Hi to everyone! I have been trading for some years through an online store and realized that it's time to find a suitable PIM system (product informatiom management system). Honestly, I have already read a lot about them and found that there are such a free options as open-source systems. For example here: https://treolabs.com/journal/treopim-pimcore-akeneo-open-source-pim-systems-in-comparison But are they really easy to use as it is described? I would be very grateful if someone had the experience with self-adapting of PIM system to their store and can share information about it.

Moreover, I am interested whether there is always a need for additional paid modules? When choosing the system from the point of view of pricing policy, I would prefer TreoPIM (https://treopim.com/). Pimcore is also very good, but expensive for my company. Please share what kind of systems do you use?