There are three types of light systems in the market: permanent wired using existing light bulbs, non-permanent wired that use a magnet to connect to the towed vehicle, and wireless light systems.
Here are a few questions to ask yourself when deciding:
1) Do I plan to change towed vehicles in the next 3 years?
This question is important because if you are having a wired light system installed, you are going to either have to uninstall it and reinstall it in another towed vehicle or bite the bullet and purchase another light system for the new towed vehicle.
2) Do I want to pay for installation or do I want to have to install something myself?
Installation time for permanent wired systems can take a few hours to install. If you have it installed the shop time can be expensive.
3) Do I want something elegant?
Non-permanent wired systems and wireless systems are very easy to setup and require no installation; however, cord management and appearance may not be for everyone. The nice thing about wired systems is that you never seem them. You simply plug in the umbilical power cord from the motorhome to the towed vehicle and you’re done.
In our opinion, permanent wired light systems that pull power from the umbilical that goes from 7-pin on the motorhome to 6-pin on the towed vehicle is the most elegant and seamless. The reason we recommend a 6-pin on the towed vehicle side is to keep your options open. 4-pin and 6-pin umbilicals all have the same 4 pins; however, the 6-pins have an additional pin for electric brakes should you tow a trailer with trailer brakes, and a pin with an always hot 12V accessory.