Both sportsbooks perform like crap majority of the time on both mobile and desktop(Using high-end machines). The biggest difference is the no-KYC requirement which is what most crypto gamblers look for in a sportsbook or casino.
I have to say running a sportsbook is not an easy business, not in just mental level and how end to end flow works, but also tech related as well. We are talking about thousands of games every single game all around the world, from very much loved football, basketball, american football, and many other big leagues to as little as table tennis and handball type of games, there are so many things every single day that you have to put in there if you are like pinnacle.
So, this means that both stake and pinnacle have a hard time with the tech stuff, it is not all that automatic constantly and you have to keep checking things out all the time, if you are lucky you will get it done, if you are not lucky you may even have errors that allows gamblers to win more than they should. Plus you have to check each bet and credit them too, you can't just auto credit them or you can miss a mistake. It is very hard job man.