Left the house the other day showing 29 degrees F on the thermometer. Rode about 75 miles using my newly-acquired heated jacket and glove liners. With the wind chill the "Real Feel" was probably more like 19 F. Made it back from the 150 mile ride with numb legs and feet but my core was quite warm, I even had a nice blister burned into the back of my right hand from the glove liner . . . pro tip . . . do NOT locate your controller where you cannot adjust it while riding, especially if you KNOW you are BURNING lol . . . love the funny looks on people's faces when they see a bike out on the road, amidst the snow and ice.
What kind of jacket are you using? I found if I wore leather or textile, that it was sucking the warmth away from the heated liner, if you get a nylon shell type jacket liner, think windbreaker, or down vest, over the jacket liner, in between the outer layer the vest, all the heat will be directed towards you, and you'll be warmer.
I've used it down to 24 degrees and was comfy. For your legs, I would purchase a set of sking bib overall pants at big 5 for about $15 bucks on sale, they work great, and are somewhat waterproof as well.
Glad your enjoying the gear.