Looking for music streamer/server...Is a Macbook Pro better than a Sony Hap Z....

I wouldn't go with a Mac or PC either. Computers, with all the capabilities they entail, are prone to a lot of problems from a sound quality perspective. More dedicated pieces on the audio side will sound better and will be easier to use as well. If you're looking for something that includes storage, you can get something like a Bluesound Vault 2. Alternatively, you can also get something like the Auralic Aries Mini and install a SSD in it. To go higher, you can get something like the Melco N1A which is a very high quality audiophile NAS/Streamer. If you have a DAC with USB input, you can stream from the USB of the Melco to the NAS. Any of these choices will be superior to a Mac option. These are just a number of the multitude of excellent options available.

Agree with Everest for the most part. IMHE, storing library on NAS and then connecting to a streamer/network player connected to DAC is the best option. The other self-contained units with internal SSD are next best approach. Cheers,
Spencer 

I recently switched from using my MacBook Pro to an Auralic Aries Mini.  As is I'd say sound quality is about on par, while the user interface (software) if far superior.  I've added an external power supply and the sound quality improves significantly.  No regrets.