As you might imagine, living in New Hampshire I get a lot of opportunities to ride in really cold weather. Some of the replies are amusing. Heated gear in the Carolinas? :lol: But some replies are spot on.
#1 - get a heated jacket liner and heat controller. I suggest Warmn Safe because they are fantastically effective, and once you start down the path of one manufacturers gear, youll probably want .to stick with that manufacturer. Warmn Safe, also sold as First Gear, is the best overall setup available. Plus you get a lifetime warranty on the heated clothing.
Get the 90 watt liner. You should never need more, an$ most likely will always have it dialed back by half or more most of the time. But, when it gets to below freezing and you add the wind chill of riding at highway speeds for hours at a time, you will want the added overhead capacity the 90 watts supplies.
Wear a thin, tight to the body, insulative and wind blocking layer over the heated liner and under your riding jacket. Keeping the heated gear snug is key to it being effective. Try it both ways, with and without the compressive layer, and youll see what I mean.
Since youre already buying a heatroller, buy a dual controller. Because your second purchase is for heated gloves. Yes, wind blocking helps. Heated grips too. But nothing is as good at maintaining your manual dexterity as full heated gloves when the temps get really low. And that is the point of heated gloves, maintaining dexterity. Comfort is a secondary consideration. Crashing because you cant operate the controls is a much bigger deal. From a safety standpoint the gloves may actually be more important, but without the jacket liner I wouldnt be out riding when its that frigid to begin with...