I've used mine in two differnet AR's. The paperwork says use high velocity ammo but I've only used CCI Blazer so far. It works fine in my rifle, but has some fail-to-feed issues in the little dude's AR.
I think this may be due to his only having a few rounds through it. I had several hundred .223 fired in mine before I used the conversion...I forgot to break his in and started him off with the Ciener right away and had some issues. I'm going to put some .223 through his rifle & try the conversion again.
Keep it lubed, just like a normal AR.
I'm going to get some BlackDog Machine mags also. Most seem to say they are more reliable than Ciener's and they are only $30-35 for a 30rd mag.
All in all, I doubt I will use it much in my rifle, but since the kid thinks ammo grows on trees he will give it a good workout!
.22LR ammo is picky. Not because of the Cenier kit but because of the nature of the round. Since a box of 50 is relatively cheap, try different ones to see which gives the best results for your AR. Once you find one that works good, then go out and buy it by the brick. A lot of .22's will have a few duds and flyers in a brick these days.
As far as the kit goes, it will fire most everything.
Best results were Lapua match ammo but it's too expensive. For cheaper commonly available ammo, I just use Remington Thunderbolts. They are cheap and fairly good accuracy. More expensive Winchesters and CCI's didn't offer much more accuracy for the $1 more per box however, your AR might be different.
I did notice my remaining 15 year old Tundercruds perform better than the currently available ones. Never had a dud in them old bricks, either. I guess Quality Control went downhill over the years.