Since there obviously isn’t any published data, I’m a little leery of getting too specific. But there are several threads out there with good info on Lever w/ heavies in the 223. Snipers Hide, 24 Hour Campfire, and asrealasitgets all used to have a few good threads on the subject.
I will say, I was skeptical and very cautious working up with it, and did a bunch of reading first. It behaves exactly as you’d expect a powder of that burn rate to. Velocities, SDs and accuracy as hoped, with no unusual pressure signs. I’m not really pushing it as hard as some guys have, stopped when I got ~2950 out of a 24” barrel. A few of the guys I shoot with are now using it in the 223 w/ 75ELDs as well.
I’ve only fired 450-500 rounds using it. So far the one possible downside I’d mention is- it seems to burn a little dirtier than Varget.
Best of luck if you decide it’s worth a try.