Streamer with built in DAC...is there much difference between brands?

The OP is asking a question similar to “Why would anyone by a Ferrari when my Yugo gets me to my destination?”

asahitoro - Well, the WiiM Ultra is a complete solution and people with many systems are happy to use it for streaming with its integrated DAC. Some also go with an external DAC. 

A WiiM Pro/Plus with an external battery-powered 5v solution will sound better than the Ultra with a good system and fairly good external DAC. The external 5v power is a great option for those WiiM devices. (The WiiM Ultra does not have this option.)

This is somewhat system dependent. For many, the WiiM Ultra as both streamer and DAC will be an easy win. 

You're asking about a device that takes a digital signal and then converts it to analog signal that we can hear.  The digital signal going to the device might be the same, but what comes out is not.  The conversion to analog is where the magic happens and the quality of the DAC and other components makes a difference in how the analog output sounds. 

Short answer is not all streamer/DACs will sound the same and there can be significant improvements in sound quality based on quality of components and level of craftsmanship.

I just received from Germany a Lindemann Woodnote Solo.

Out of the box using as a dac replacement and preamp substitute it really has impressive soundstage..Will try as streamer in the next day or 2.

The Wiim with a Teddy Pardo power supply is really good….the Wiim products as a streamer to a dac with their very good app is definitely the way to go. I sold a dac recently to a local guy who was using a silent Angel as a streamer and was having problems with the song dropping, another problem he has is bad internet with a 6 to 10 speed. I gave him the Wiim pro I had laying around, cured his problem with all his streaming problems. I went the expensive route and have the Meitner MA3i dac,streamer and preamp built in a one box solution. For the last few weeks I have been using the Meitner hooked directly to my First Watt Sit-4 amp to the Volti Audio Lucera speakers and it’s looking like I will never change it my Pass Labs preamp went to the closet for a long sleep.When I was using the Wiim product as a streamer I had no complaints..