A heating pad I would think would be harder to fit into your groin area than a rice sock. Plus, you have a cord that has to be plugged in for it to heat up limiting your mobility. The pad makes for a better pumping tube heater if I were to put a use to it (Unless, of course, the woman in your life needs to use it). If you could make it fit your groin correctly, and get an extension cord, I think it would work fine. The rice sock is nice because it conforms to your crotch a little nicer than I would imagine a heating pad could. Also, no cord which is a pretty nice bonus. But if you don’t have a microwave, heating the bastard any other way would be more trouble than its worth IMO.
Let me make a suggestion. Search for infrared lamps in this forum. People have raved about it, and I have first hand testimonial of it’s use. It’s fairly cheap, can heat deep into the skin, does not go cold, can heat right through a pump’s cylinder, and covers a wide area of the crotch. The downsides are that you will also need an extension cord if you want to move it, and you need protect your testicles from the heat. I would imagine that type of heat could definitely do damage to your sperm count over time.
Phoenix