Thought I'd update this thread.
Having received some very useful and helpful information from
@Sara_H and Woosh bikes and also of course
@Salad Dodger s great post above, I plumped for the
Woosh Sant Ana CD for my wifes birthday which was this Sunday just gone.
Woosh changed the seat post and saddle for me to lower the whole thing and my wife is comfortable on it.
On Sunday we went out and did 16 miles and yesterday evening we did 12 miles. Due to health problems she would have been unable to do 3 miles previously and would have collapsed in a heap if she'd tried, but having the assist on the electric and the option to increase the help level when and if required meant that she not only could do the increased distance with ease but also had the confidence she could do it. We've done some hills and some long steady inclines and it's been coped with admirably.
Last night we rode into town which involves going up a hill which my wife said to me, when we reached the top, that she would never have thought she could have ridden a bike up.
So if you're finding it a struggle I wouldn't hesitate to recommend an ebike (I know it's very early days).
It's been about 4 years since my wife has been able to come for a bike ride with me, now she can again and everybody is happy.
Edit -
@Salad Dodger reference the range on the battery. On the battery there is a charge level indicator and there is one on the trip commuter too, the indicator on the battery has 5 levels whereas the one on the trip computer has 4. The suggested potential milage is 60-70 miles, now as you say this would have to involve a perfect set of circumstances, however on the two rides done so far the battery indicator has dropped by 1 bar and the trip computer indicator hasn't dropped at all, so I'm pretty confident we can push things a little further