All depends on the price you want to pay, how loud you need it, if you want portability or not etc.
I'm not sure Spotify or streaming audio will give you the best sound(unless they are using lossless these days but I doubt that), if you are going to splash out on a nice speaker do it justice with some lossless audio(flac) from time to time atleast.
This guy is arguably the best youtube expert on them IMO:
https://www.youtube.com/user/clavinetjunkie
He uses binaural sound so if you listen with some headphones you get a good idea how they really sound and then you can be your own judge as it will come down to personal taste.