Or 15.5 potentially. I believe that the popular Xiaomi m365 does 15.5mph

I agree it is not super-fast, but for use in urban environments 15mph would be pretty usable I reckon. My pre-lockdown commute in london on the tube would take about 35 minutes door to door. Walking it is 4.2 miles, cycling 4.9 miles. lets call it 5 miles for sake of argument.

So for a 12.5mph scooter it would be 24 minutes. For a 15.5mph scooter it would be 20 minutes.

That is pretty good I reckon - it takes me 10 minutes to walk to the tube station, so to be half-way/almost half-way to work before I would have even got to the station would be pretty decent I think.

Only thing is, this all makes sense when it is glorious sunshine and warm outside. It might be less appealing in December :-)

The law is out of date. e-bikes are just cycles under the road transport act, electric scooters are 'mechanically propelled vehicles' - i.e. just like cars and trucks.

In theory a scooter would be legal on roads if you could convince the DfT you met the safety regs, had a type certificate, license plate, VIN etc - it would still be illegal to use on a bike lane and I don't know that anyone has managed to do this!