The only one I have is Rl-15.. Havent really played with it enough to make my own opinion yet, but from what I read people love it in 7.62x54 and .308 (I read thats the powder used in the military M118 .308 "sniper" rounds)
The only thing Ive shot it in was a Arisaka and my Finnish Mosin. The Mosin liked it, the Arisaka not so much (but the Arisaka data was a little "flaky" and I dont trust it. It was from Guns & Ammo mag, but the minimum load was producing pressure signs)
I just have a hard time using it.... In theory it should work in most of my calibers, but theres no good data...
IMR-4895 will be my rifle powder (If I can find any...)