Also never used the cellular function so that was a waste of time in hindsight - just tethered it to my phone.
I had an original iPad mini and now have the smaller iPad pro - I used/use them both mainly via the cellular connection, as if I'm in the house I use the laptop, they're for use outside the home, or at least were for me.
I just don't like multiple sim cards - can't fathom the value of PAYG and don't want another monthly direct debit so I got one good contract (27gbp pcm for 24gb data) and whenever I'm remote I'll tether. But usually I was somewhere with WiFi i.e. a studio or a train.
I had an original iPad mini and now have the smaller iPad pro - I used/use them both mainly via the cellular connection, as if I'm in the house I use the laptop, they're for use outside the home, or at least were for me.