I've been using a 250watt Chinese hub motor kit on my tricycles for well over a year and I've got nothing but praise for the setup. For a lot of the time I've been using the e.kit I was doing pamphlet deliveries to around 225 households in the rural town where I live and my round took in one of the steeper hills in town. I used the e.hub to provide assistance to my pedalling because pamphlets and flyers weigh heavy (5-8 per household X 225) and even with the extra weight of the two SLA batteries the e.hub made a big difference to the speed and ease with which I could complete my deliveries.
The controller that came with my kit can be set for 200watts as well as 250watts and most of the time I ride using the 200watt setting. I don't have either a speedo or odo on my tricycles so I can't give you any speed or range data, but the simple fact that this e.kit is doing what I want it to do with complete reliability has to be significant.