A few comments on my first JustPlug installation:
First, as you can see in the photos, I used some of their street lights. It looks great! There is no doubt that not worrying about the LED power supply as far as using the correct resistors is a great benefit. However, the thought that this eases installation is not true. First, the wires are way to short to be used on the streets. They would be perfect for doing a building interior, but wire will have to be added to get to the main board. And you want that board at an easily accessible spot so that you can utilize the dimmer features. The wires coming from the lights themselves are EXTREMELY delicate, leaving one to break during installation and I had a heck of a time finding what the problem was. Also, the red side of the plug on my system was not working the greatest.
In addition, the dimmer control board needs an overall on/off switch. I'm going to look again because I can't believe it doesn't have one (I'll put my readers on this time). As with anything, there will be a learning curve here. Again, this would be great working on a building, at your workbench. But installation on the layout will take a well thought out plan to avoid multiple trips under the layout.