I have the BG-75 (the older one with DC input), they're for home practice and playing along with acoustic guitars really so may be perfect for your acoustic circle, especially given the BG-80 can be powered by a decent power bank. They sound great in this application and although I own some very nice small rigs the PJB is my favourite, they get a full sound due to the passive radiator design (that's the "something clever" bit you wondered about!) so need to be placed in front of a solid object, they don't sound half as good in the middle of a room and the low end drops out.
You're going to be disappointed if you expect anything more from them tbh, very useful little things and they do sound brilliant if your requirements match their capability. They can also be a gateway drug into further PJB purchases so you have been warned.