If you are tackling those typically tough Devon hills the Cyclamatic will be found wanting since it's one of the lower powered e-bikes. The member who likes them the most and has a couple lives in the Eastern counties where the going is fairly flat. The Juicybike mentioned above is a better choice for hills.
Basically if getting a hub motor bike aim for a 36 volt one, not 24 volt. If you are prepared to spend more and get a crank drive bike where the motor drives through the bike chain and therefore uses the bike's gears, a 24 volt system will be ok. This latter type of bike is a favourite in the Devon area since it handles the steepest hills best, but they are mostly quite expensive.
I know that it can be difficult to do if living in Devon, but it's always best to try out any e-bike you are considering before buying to make sure it's suitable, and worth travelling to do that.