i bought some flourite 5-6 years ago that I just dumped in the tank and it wasn't messy at all, nothing that didn't clear up in 3 hours.
I bought some flourite 4 days ago and 3 bags of it in my 58 made it look like the whole tank was full of severe diarreha, the flashlight only penetrated about 3 inches in, 2 100% water changes later (while stirring the substrate), it's still crappy, but it's a grey cloudy and doesn't look like fecal matter anymore. There are some clumps in the substrate that looked like some flourite held together by dirt, seriously.
So I think sometimes flourite needs rinsing and sometimes not.
Profile Clay Soil conditioner can go without rinsing, my crypts did great in profile. A lot cheaper too, but seems to be only seasonally available at stores, unless you buy the aquatic soil version for like 5 times the price