I use both Mini and Big Jambox depending on location. Mini is suitable in an office or quiet area (while delivering decent bass) while the Big Jambox lives up to its name and works best loud like is needed outdoors.
Both have relatively long lasting batteries. At low volume the Mini Jambox will go for two days.
One annoyance I have with either one is the loud voice prompts whose volume you can't turn down.
Going nowhere @ 220 ft