223 whose or 556?

I doesn't really matter.  If you could shoot as good as an AR-15 (AR-14 for the Joe Biden supporters) you would be concerned with the difference.

It does not matter untill you start to reload.

Both are fine, 223 Wylde has a slightly tighter tolerance than a standard 556 chamber and is intended to be beneficial for accuracy. The cost of a barrel is negligible compared to the amount of ammo you'd need to run through it to wear it out. 

I honestly prefer 223 whose but they are extremely hard to find.

556 is the way to go...……...

I am making an extra upper just have it.My go to AR is a standard 16 inch Government profile barrel with a carbine length gas system. In hindsight I should’ve gone for the mid length but that barrel is probably going to last easily another 10,000 rounds. This build is just a scratch an H I’ve been having for a few years. My other one is a full 20 inch barrel for long range which I don’t use anywhere near as much.

 To be honest your standard 5.56 barrel with M4 feed ramps will be fine. I pretty much only shoot federal XM 193 and XM 855 exclusively. If I’m shooting for accuracy I will use Black Hills OTM’s.

Follow BBean's advice.

Honestly, I have rifles with barrels from 1992 that have 14,000 round through them - and are still not showing any sign of wear or tear.  I would not have 1/4 of that through them if not for match shooting.  Unless you have a full auto, lots of friends and a pickup full of ammo crates -  or shooting NRA highpower rifle competition with an AR - very doubtful you will ever wear out a barrel.

When you see the word "WYLDE" then fire both  5.56 or .223 `til you run out of ammo in your AR-15.

Not familiar with .223 "whose" but will vouch for this barrel to fire all 5.56 and .223.

NOTE: If you want a more detailed answer...just ask because these hit and run questions are really bothersome and a waste of time answering. Realizing that some of the people that frequent the hunting section have very limited attention spans.