I would strongly recommend keeping collective friction very low, especially at low-level.
Chasing a fox through gullies and ravines during some authorised NOE I over-enthusiastically over-cooked it, hit retreating blade stall (in a UH-1B), snap-rolled well past the vertical - and the only reason the aircraft auto-recovered is that the g snapping on caused the collective to drop for the floor.. .Why did I not have the collective friction done up? A smart chap called Laddie Hindley was my QHI for one trip and recommended I not have it wound on at low-level. I took his advice, even though I'd promptly forgot exactly why... and so lived to tell the tale.