So far, we have not had a chimney fire, and the remover seems to work well. Every spring the DH climbs up on the roof and uses the brushes. I personally think he just like climbing on the roof.

In the fall, we tap the chimney, it is all exposed, both inside and out, and see if anything moves. If we hear any fall out, the brushes come out and it gets cleaned/brushed again. Then we remove the re-burner and clean behind it. Which I generally will do anyway.
I have no doubt that a chimney sweep knows better. I wish I had a friend like that. We are only trying to be economical, and do it all ourselves.
We have a quart sized tub that is creosote remover, made by rutland products. I know they also make individual sticks, that you add when you first light a fire. It has always worked for us, with proper cleaning, of course. I am a fanatic about the 12 x 24 glass being clean. If I must heat by fire, I want to see it!
Nancy
You never know when an Angel is watching you...