I must say that when I was in rehab ('84) all of the paras who were halfway fit could out run the power chairs. It was in Orlando when it was growing a lot. Lots of smooth, flat pavement. Then of course the batteries were even crappier than they are now.
All of that is ancient history now
Things moved on. They still preach the same crap though. You CAN use a manual provided you dont mind being exhausted, fingers all cut up and hard skin, or covered in crap. With destroyed shoulder or elbow joints long term. And only on the flat, no hills, no cross or transverse slope, while not carrying anything such as a camera or tin of coke, as long as the ground is smooth and only for short distances... Massive fight getting into or out of a car.
With todays footpaths, the stupid little caster wheels on manual chairs, and no suspension even going up the hill out of my street, to a pub 1/4 mile away along broken footpaths is a nightmare. Even if its not raining or freezing cold. And by the time you arrive, no strength left to do the 15 degree ramp... So what manual chair users often do, is mentally make 101 excuses as to why you are not going to the pub, bank, etc today... Same thing with trips to the beach, walking your dog, going out to do a bit of photography, popping up the road to the takeaway. The result is that you miss out on life and make excuses to yourself for why you are not in the local park for an hour while eating your dinner. They will try to add power to manual chairs. They will buy power addons or power wheels. Which always makes a useless powerchair. Anything but actually try a real "powerchair"...
Once you do manage to persuade a para to "try" a powerchair, they are always converted. The beloved manual chair is kept, but seldom ever gets used again. 20 years on, mine is in the garage, flat tyres, and covered in dust. I wont even consider it for backup use as its harder to transfer into, unstable, uncomfortable and my life goes from active/normal to extremely restricted!
Basically its £££ sat there for no good reason.