The sound systems and dub camps still use 18s, the Big Ben sounds like a good idea to me and I don’t think they are overly expensive now , I used markbass 15s for a long time and they really do the deep low end well, I use a barefaced big baby now which sounds great too, I’ve always fancied the Barefaced Dubster , that would be perfect if you could get one, not sure if this helps mr B