I did the suck and refill method at 30, 326 miles.
I used a radiator Fluid Checker for the suck procedure because I had an old one that never use anymore.
The tube size fit into the area where the hose is.
First suck: I had compressed the ball before inserting in the fluid, came out clear.
Second and Third suck: I compressed ball with tube in the fluid and it got milky. Pumping air in the fluid I guess.
Stored in a pint jar - it was very milky at first, probably from the procedure of compressing the ball while in the fluid (not do that again).
Eventually settled out to a very thin layer of white (milky) on bottom of the container. Whatever that is, I do not know.
PS: I plan to do the procedure again at some near mileage (hoping if any mix occurs with old fluid left in hose and clutch, will get some of that out).
That said, read on GOOGLE someplace: A mechanic said, you don't get much mix. I guess fluid is not circulating, just hose and reservoir is taking in and out when needed.
PSS: Anyway, I am not going to worry too much about it - relying on the guy that has 150,000 miles and never changed it.