Don't get a 1x red dot. A complete waste of money.
Here's why:
1. doesn't work without the battery. Yes, the T1 batteries last 5 years, but if something happened to the circuitry or the battery, you're hooped.
2. no magnification.
I highly recommend one of the 1-4 scopes with red dot, like the Bushnell Elite 1.25-4 with 4A illuminated reticle. At 1.25, it's functionally the same as the more expensive T1, but it will work with the red dot turned off, and has magnification when you need it. It's just sensible economics. Especially for a 223 semi-auto that has long reach, why waste the money on a short range optic? IMO, the T1 and other x1 red dots are for shot guns and other short range guns.
I don't like the idea of removing a CQB scope to install a long range scope, I like my scopes to never come off the rifle.