First let me say that I shopped in the store and was able to connect with my phone listen to my own music before buying. The environment is noisy, but it did help. Secondly I bought two units (this was the first), took them home, and returned them each the next day before settling on a third. Best Buy handled this smoothly. Sometimes brick-and-mortar beats online shopping.
I looked at the Beats Pill+ for $180, the Sony SRS-XB3 for $130, and the Bose Soundlink Mini II for $180, in that order.
The Beats had good volume, good sound for bass-heavy music, bass boost, and USB-to-lightening cable power. I returned it for less-than excellent sound, and I was disappointed that the lightening cable was only for power - I had thought it would be used for high quality connection to my iPhone, but that is by bluetooth like the others. Also, the sound effects when turning it on and off were loud and obnoxious. Back it went.
The Sony had very good volume, good sound for all music, bass boost, but the power is by wall charger with proprietary jack. This was a deal-killer for me, since I want to be able to charge it in the car. For sound alone this may be the best of the three, but back it went. It's also the largest of the three.
The Bose had the lowest volume of the three. I generally think that Bose is highly over-rated, however, the sound is quite good considering its size. Reasonable bass, midrange, and treble. No adjustments available. Power is by USB-to-miniUSB, which can be plugged directly into the speaker or into a very nice charging cradle. Voice prompts are useful and not obnoxious like the Beats. There is a rubber pad on the bottom which is good for a table top or dashboard top.
All three units are heavy for their size. None are miraculous for sound, since physics limits what can be done with that small size. For household or outdoor use, the Sony may be the best. For overall flexibility including the car, I chose the Bose. Beats may be good for bass-heavy music, particular in the Apple world.