I've used PC-ICE clear while I was on my H50 mod. All of PC ice's fluid come in clear and require end user to drop a dye bomb. There is no real benefit to using a premixed coolant. I've got some images of my drained H50 fluid(PC-ICE clear) and after leaving the contents in a metal bowl for a day, I could see some cloudy moulds forming. Easily suspect to being microbial/bacterial growth.
Performance wise, distill's better. Martinsliquidlab had performed a test...actually head down to the watercooling sticky and read up down below in the FAQ section.