Definitely a must :)
My kit has a little over 4900 km made in 2 years. The customer support was always helpful, even before the purchase, as I had no idea exactly what model I need to buy. In total 5 spokes broke, but they were replaced on warranty and even paid the bike shop to do it. A very good experience overall and a cheap, but quality DYI. The fact that you can return the bicycle to the original state is a plus for me. Easy to use, easy to install, easy to take out the battery to recharge it in the house.