I have shot both the TBRC and KKM...I currently have a G19 running with the KKM barrel/comp. The KKM does not like low power ammo, e.g. Fiocchi 115gr, Blazer 115gr or Magtech 115gr. In my experience, this ammo causes failures to eject (stove pipes) and failures to feed. My Silerncer Co./TBRC micro also prefers higher power factor ammo.
Both of my set ups run well with MEN 124 Nato, Winchester 124 Nato and Speer Lawman. Additionally, Fed HST, Fed HST +P, Speer Gold Dot and Speer Gold Dot +P run well with both.