Warm n Safe. Heated Jacket liner, Heated Pants liner. Jacket is waterproof and the pants are windproof which adds another layer of protection from the cold air getting in. They are not insulated, so you can hop off the bike and walk into a store and not feel like you are melting.
I also have heated gloves. With those, I use heated grips too as the heated gloves don't heat the palm.
I also have heated socks, but only ever used them once. Find I don't need them as my boots are warm and I guess warm legs do the trick.
I use a 2-channel controller. It's wireless. The controller is mounted on top of the left hand brake master (Yea, I eliminated the back brake pedal and put a lever on the left like a scooter) One of the channels controls the jacket. The other controls the gloves and pants (and socks if I used them) This works nicely as I typically need different settings for the jacket and gloves. The pants seem to work well when linked to the gloves.
The way the controller works is by using a pulse width modulation. Basically, the controller pulses many times a second. The length of time the pulse is on vs. off is what varies. By controlling the heat this way, you actually reduce the load on the electrical system since power is only flowing certain times. I've run my heated gear and grips on high for a fairly long ride and saw no issues with the electrical system, so it seems to be OK on the NM4. All those LED lights gives us a lot of extra juice than the other NC bikes.
I installed a SAE jack in the passenger footrest on the left side of the bike. I use it for the BatteryMinder, my air pump, and for the heated gear. Easy to reach from the seat so I can connect and disconnect while seated. Just one power connection.
A controller built into the jacket takes care of moderating the heat on the two channels. Internal wiring that can be accessed by zippers are used to send the power to connectors at the wrists to connect the gloves and to the waist to connect the pants. The pants have another set on connectors at the ankles to connect the socks.
If you don't need a connector, it can be tucked into a zippered pocket to keep it hidden and safe. With the wires all tucked away, the jacket looks like a nice windbreaker, so you can use it as an off-bike light jacket. Great for touring as I don't need yet another piece of clothing.
Here is what I have:
I also have a 15 amp harness that connects the battery to the SAE jack. The one I have came with the BatteryMinder, but it is similar to this:
This stuff isn't cheap. However, when the temps are below 60 degrees, I usually toss on the heated jacket and gloves. I might not power them, but what is nice is that I can at any level of heat I want. I add the pants when temps might get into the 30's. Other than that decision, I don't need any other layers. I wear boxers and a long sleeve T-shirt typically under the heated layer. Over it I simply use my Klim riding jacket and pants. You never feel like the Michelin Man. The liners are thinner than a fleece.
I have a friend who prefers to wear a 100 weight long underwear under his heated gear, but I felt it was too warm when going indoors (like for lunch) It is an option for those who tend to be cold.
The collar of the jacket is heated, but in the real cold you need some kind of gaiter over the jacket to seal up into the helmet. I use a Rukka windblock version that is really thin, but works great.
OK, I'm starting to write a book here. If there are any questions, let me know.