Streaming: WiFi or wired??


Looking to get a new streamer for a system based on Kii Three. WiFi signal is good but I’m also told that wired is always better. Specific streamer advice also welcomed; (no need to rip CD's). Thx in advance for any/all advice!
benchwarmer
If you can always go wired. It is just the way wireless works that makes it inferior. Main point is that wireless data transfer drops off as the distance from the router increases. Wireless is also susceptible to all the other electrical signals in the building. Take a Bluetooth connected device as soon as I turn on my microwave the connection drops. If you are playing a high res file and don’t want any compression go wired. For my player I just use my MacBook Pro into a usb decraper Into an external dac. It works great, qobuz sounds amazing with my setup. Yes my MacBook is cat7 connected.
@snowbuffalo I used iFi power supplies on my modem and router. I recommend them. If you do try a low noise PS for you modem/router, I'm Interested to hear whether they make a difference for you. 
Two comments.

First, @guy-incognito, regarding how much sense it makes to install better cable than your ISP service speed needs, keep in mind that upgrades do happen. I recently went from 100Mb internet to gigabit and had to replace two runs of old Cat-5 (not Cat-5e) cable in order to get the new speed at my desktop. If I hadn’t been quite as cheap with the cable back when I got 12 Mb DSL, I could have saved myself some work this time around.

(Of course, I started at 300 baud in roughly 1980, so that’s been quite a change in connection speed over the years.)

Second, @snowbuffalo, crosstalk in ethernet cables has nothing to do with crosstalk in stereo separation. Ethernet cables have 4 pairs of cable inside them and they are talking about the interference between those pairs (crosstalk). There is no stereo separation in a digital signal until it is decoded in the DAC. Only then can you have a stereo separation problem. Cat-5e cable can do gigabit speeds without problem, though Cat-6 might be better for long runs or a particularly noisy EMF environment.
Agree with many of the above who point to implementation. I also believe there is no absolute and x is "always" better.

Nice little video on the subject matter (and the Aries G1 streamer by Auralic) by a reputable reviewer:https://www.youtube.com/watch?v=Cqd8UXCGU0s
Mahler123 is right.

Both wired & wireless will work excellent as long as they are working within their limits. The chances of wireless dropping packets and causing re transmissions are a bit higher than wired, especially if a lot of wifi devices are sharing the same band. Moving to the 11ac at 5G bandwidth may reduce those issues, unless you live near an airport or anywhere where radar signals are present.  This may cause the AP to change bands continuously (DFS).  Also, with higher frequencies (at 5G) , your signal degrades quicker so distance becomes more of an issue.  This is laws of physics and you just have to live with it.

99.999 % of the time, both will be fine :-) It is really a choice of convenience.