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.

Yes sbank, a NAS and streamer into a DAC as you're suggesting works very well. It can also come down to how technically savvy someone is as well. The problem I have with Macs or PCs is the knowledge and tweaking it takes to sound their best. To get great sound out of a computer, you often need specialized software to shut down system processes and maybe jitter reducers/reclockers to get the best out of the USB signal. Then you're still dealing with a computer in the room, etc. Many other approaches simply sound better without all the tweaking.