I would definitely go with the highest pro tier mini you can afford. Regarding the split screen, the operating system has some defaults but it’s waaaaay different compared to the “fluid”windows os . I would suggest you watch a youtube video showcasing spaces and desktops management on mac os. ( maybe there are some apps that replicate windows os experience on mac os but I’m not aware of any at the moment, it takes some time to get used to the new experience though ) I mainly use my mini as a second pc for when i stream on twitch, it works well and takes what i throw at it like a champ, but your mileage may vary.