Other benefits of the front hub motor are;Thanks for all your responses. Lot of very useful info for me to consider!
I didn't even realise that 27.5" rim was different from 700 rim! That's confusing and a bit limiting!
I did look at the various Woosh kits and I really like the look of them but they are maybe a bit more expensive than I was wanting to pay for my first attempt into the world of ebikes. But they do seem the simplest design with the best support so I definitely won't discount the option..
The point Woosh makes about the rigid front forks being unpleasant to ride makes me wonder if I'd be better going for a used Carrera Crossfire 2 as I've seen a few of them for sale for around £100 as well in recent weeks. I believe these are a bit heavier than the Subway, but I don't have any stairs to carry it up so that wouldn't be a problem. They also have standard disk breaks rather than hydraulic which might simplify things a little. Any thoughts on that being a better option than the Subway?
My original thinking was that a front motor would be easier to fit but I might now consider a rear hub motor as I'm getting the sense that most people prefer them.
Thanks again for all your comments and help, very much appreciated
You aren't messing with rear gearing at all so whatever you have at the moment is fine.
By having a front hub motor your rear spokes are full length to give more spring in the rear wheel and comfort
Steel forks and a low power hub motor means you you shouldn't need a torque arm to secure the hub motor
Your bike becomes two wheel drive as you have traction on both wheels which can help on loose surfaces
It can be a pain to remove rear hub motors to deal with punctures which becomes much easier on front hub motors as there is no gearing to get in the way
Tyres wear at a similar rate front and back
Some people like the heavier steering of a front hub motor it can feel more stable
The motor is simpler without a freehub or freewheel thread so less maintenance issues and things to go wrong
You can return it to a normal bike easily just by swopping back the original wheel and removing the battery
You don't have to compromise the rear dropouts of the main frame to get a rear hub motor in
The bearings of the hub motor get an easier life at the front as much more of the riders weight is at the rear typically 60-70%
As for the disadvantages I don't think hill climbing traction is a problem on low power front hub motors. A huge amount of pre-built ebikes have front hub motors and its not a widely reported problem and a large percentage of those have smaller wheels which are more torquey (if that is a word). The Subway is basically a hardtail mountain bike with rigid steel forks instead of suspension, being a mountain bike you can fit big tyres on it for comfort like Schwalbe fat franks or similar (and these will also give you more grip), comfort grips and of course a sprung saddle or even suspension seat post. Lots of ways to improve comfort without the additional expense, weight and maintenance requirements of front suspension.
I personally wouldn't choose a Subway for a rear hub motor conversion. I think if you are going the rear hub conversion route there are better options. On some of the recent Subways they have perforated rear dropouts rather than solid rear dropouts so removing material is more risky. You will definitely need a torque arm, maybe 2 which are a pain to work with and time consuming plus extra money.
A Subway with a front hub motor is convenient and easy to live with I think. It's almost fit and forget. I'm a heavy rider so I actually get much more punctures on the rear than the front but I realise you aren't so heavy so that probably isn't an issue for you so I haven't put that as an advantage of front hub motors but for a lot of people that is especially those that overload the rear with shopping or have a rear child carrier.