I would try it. What do you have to lose? Jeffreybehr is quite knowledgeable about figuring out the most appropriate gauge to use. So is S23chang. You might ask them, or just wing it. As I said, we went from 15AWG to 8AWG, and suddenly got way more music, better soundstaging, and a much more open & relaxed sound. The difference was hardly subtle.
Gmgood1's thought about trying DIY--if you're so inclined--is a great idea as well. Alternatively, I decided to try a good pair of factory silver speaker cables, since buying used makes it easy to re-sell at usually no cost. And we're very happy with the move.
Regards,
Howard