I've owned a couple of them in the past, simply because when the Rem 223 came out, a lot of people switched over to the much cheaper cartridges and as Ganderite says, almost identical performance with the bullets available at the time and seeing as my finances back then were tight, they were going cheap.
The first 222 mag was a lovely custom rifle, built on a European CZ action that had a steel mag well and steel magazine. It was very accurate and I used it exclusively on Coyotes for at least five years. I miss that handy/accurate little rifle. The next one was a factory Remington 700 SA, in a McMillan stock. It was even more accurate than the CZ but wouldn't shoot bullets over 50 grains well, unless they had a flat base.
Getting brass for those rifles was also tedious and even when I ordered it through my local gunshop, it took months to appear.
If you can find a decent source for brass, go for it. It's a great cartridge and if it's possible get the barrel with a 1-8 twist to utilize the extra case capacity with heavier bullets.
