No, I didn't find that it built up at all, but since the silicone is non water-soluble, you would need to low-poo about once a week.
The only thing I found with it is that if you want to use this condish as a leave in, you need to firstly rinse all of it out and then add a little extra to leave in. Idk, it is just yuck if you only partially rinse it. No idea why....
And yes, I'm so so so glad they came out with big bottles
~ BIG *sexy* CURLS ~
Conditioner/Co-wash/Leave-in: Garnier Fructis Nutri Repair/Organic Instinct
Styler: Garnier Fructis 24-H