A very late reply but I've had two kits from around 6 years ago.
I ride my bikes every day for around 6 months each and I'm very happy.
HOWEVER, in that time I've had one new controller, one motor cable, one main cable and one LED display but personally how much stick I give them I think that's expected and the bloke I got the parts off sold them to me quite cheap - around £30, £10, £15 and £20 compared to the hiked prices on the Cyclotricity web page.
My main problem is that I've now gone through 3x 36v 11ah bottle batteries but this could also be my fault.
They have never been out of a garage in all weather conditions and when I get to work I've never took them off.
This week I have bought 2x Green Cell 36v 11.6ah 'dolphin' batteries which just lift of the rail and they are staying indoors when I'm not riding so let's see how they last.
Now the good news is I thought Cyclotricity parts were their own but I've found out by accident they're not.
If you go on eBay they come under KT Systems and I think Bafang also use the same cables (they look the same).
Next week I'm thinking of buying a spare motor & main cable plus a controller because I depend on my bikes to get me to work and back.
Both of mine are 36v front wheel 250 watt.
I did have a 1000 watt rear at one time but it was way too fast.