From experience, JBL has worked in my upgrade scheme. That's to say, my JBL speaker upgrades over time have integrated well with retained JBL speakers. Thinking about this aspect might support a system for music, as well as movie sound where speaker performance on music is very important. In other words, you can upgrade mains for bigger sound and still have tone consistent with center, and surrounds. I once used JBL Control 5's for front, center, and surround. Gradually, I replaced these, one or two channels at a time, all the while having surround sound that was very seamless. This is good because, no matter the sub, you might find yourself constantly adjusting its output to sound right for particular recordings.