I haven't found that much difference in the slower vs. faster burning powders in the .223. In my experience, my attempts with H-4198 proved to be unsatsifactory in the velocities obtained, nor was accuracy that great. But I had acceptable results with many other powders including Accurate 2015, 2230, 2460, 2520, SRB-118, 2200, Winchester 748, Hodgdon H-335, H-4895, Varget, and CFE-223, IMR-4895, IMR-4064, 8208XBR, Ramshot TAC and Reloder 15. My current favorites are Ramshot TAC for 40 and 50 gr bullets in all rifles, Accurate 2015 for 40 and 50 gr bullets and Hodgdon Varget for 55 gr bullets and heavier. These all work well in both my 1 in 12" twist bolt guns (22" and 26" barrels) and my M&P 15 Sport (1 in 8" twist, 16" barrel). If you want to try one powder with clean burning, consistent metering, good accuracy and velocity, give the Ramshot TAC a try. My second choice would be Accurate 2015, although it doesn't meter as well through a powder measure as the ball powder TAC.
Truth to be told, I could probably be just as happy with Accurate 2230 or 2460, the new CFE-223, or even good old W-748. The new 8208XBR shows promise, too. If you want a versatile powder, H-4895 works fine in a lot of different calibers and also excels in reduced loads in many cartridges. You can load a lot of cartridges from the .223 up through 30-06 with decent results with H-4895.