Aura Sand recommendation/advice

I am looking to pick up a good fancy play free floating slider and the Aura Sand seems to be a popular choice. I was wondering what the differences were between the regular, slim and slim pro versions and which version you would recommend for somebody relatively new to this kind of slider (I've had a couple super cheap ones that come in the cheap packs of like 5 different kinds of fidgets, but I don't know if those really even count). Any P or advice is greatly appreciated! Thanks in advance!