I don’t have any preference when it comes to game based learning platforms. I just like anything that I can get and use for FREE. One of my students asked me which of the following are the best game based learning platforms: Quizziz, Kahoot!, Socrative or Quizlet and so forth.
Personally, since I am a bit slow in learning new thing especially related to technology, I would just stick to one platform and only move on to the other platform AFTER I have really master it. So for the time being, even though I have created an account for Quizziz, Kahoot! and others, but basically I am comfortable to use Quizziz and thus, I use it often than the other.
For Kahoot!, with the current situation i.e. COVID-19 pandemic, it offers for the new user PREMIUM feature for free. Yup. But for those who have already an account, you have to pay for the PREMIUM feature. I don’t know how long the offer might last though.
For Quizlet, it has this flashcard feature. It might be suitable for mix-and-match activity and such. In my case, it is not that suitable for UG or PG courses. But I still recommend it to my students who will teach school kids in the future.
For Socrative, it is similar like Kahoot!. It is not free though for special or premium features. It is free for 50 students per room with limited other features. Somewhere in March 2020, its CEO declared that teachers can use Showbie and Socrative for free until the end of July 2020. But it caused sudden consumption traffic and overwhelmed the system. So, it is reverted to the original plan rather than unlimited access to their platform. 
For Quizziz, it is still FREE. It has new features that I like (but still learning to get used to it). So for now, I will stick to what I am currently using.