OK, so I'm ready to buy a new combo amp. I've narrowed my choices to a handful based on power and costs. One issue that I need more experience in my decision is...one 15 inch speaker or two 10 inch speakers. In my 25+ yrs of hobby-playing, my only speaker experience is with a single 15 inch. I know nothing about a two 10 inch set-up. I would be open to knowing the difference between the two choices. Anyone feel free to weigh in your opinions on this subject.