I bought my S1 Pro + battery on March 22nd, 2018 and just applied to get my backpack. Can't wait to get it. LOVE my S1 Pro. The mixer in it is super!!Use the Line out to connect to a 200 watt powered sub then crossovered to another 2-way 260 watts speaker which I call my tower-of-power and these have NEVER sounded better. I'm seriously thinking of replacing my T-o-Power by the L1 model 1S with a B1 Bass...using the mixer on the S1Pro. What do YOU think?