For a small, portable bluetooth speaker, I think the Boom 3 is a solid, well made speaker with a clear and fairly loud sound. Battery life has been pretty good. I think UE's definition of 'deep bass' might be a bit different from mine. The Boom 3 is understated in the bass but very clear and punchy in the mids and not too thin in the top end. Two of these in stereo sound very nice. The app, however is a bit of disaster and I have found I have to completely power off my ipod everytime I need to re-connect. Sometimes the app won't recognize the device even when it's connected to the ipod/iphone and playing. Also, the Boom 3 fits into a bicycle drink holder/bidon cage. Apart from being a bit light on bass, I've been very pleased with the Boom 3. While it doesn't sound as nice as the Bose Soundlink, it's way cheaper, waterproof and has a much longer battery life.